Add INLINE_SYSCALL_RETURN/INLINE_SYSCALL_ERROR_RETURN

Add INLINE_SYSCALL_RETURN/INLINE_SYSCALL_ERROR_RETURN

For ia32 PIC, the first thing of many syscalls does is to call
__x86.get_pc_thunk.reg to load PC into reg in case there is an error,
which is required for setting errno.  In most cases, there are no
errors.  But we still call __x86.get_pc_thunk.reg.  This patch adds
INLINE_SYSCALL_RETURN and INLINE_SYSCALL_ERROR_RETURN so that i386
can optimize setting errno by branching to the internal __syscall_error
without PLT.

INLINE_SYSCALL_ERROR_RETURN is designed to take the negative error
number returned from the majority of Linux kernels for which negating
is a no-op with INTERNAL_SYSCALL_ERRNO.

With i386 INLINE_SYSCALL_RETURN, INLINE_SYSCALL_ERROR_RETURN and
i386 syscall inlining optimization for GCC 5, for
sysdeps/unix/sysv/linux/fchmodat.c with -O2 -march=i686
-mtune=generic, GCC 5.2 now generates:

<fchmodat>:
   0:	push   %ebx
   1:	mov    0x14(%esp),%eax
   5:	mov    0x8(%esp),%ebx
   9:	mov    0xc(%esp),%ecx
   d:	mov    0x10(%esp),%edx
  11:	test   $0xfffffeff,%eax
  16:	jne    38 <fchmodat+0x38>
  18:	test   $0x1,%ah
  1b:	jne    48 <fchmodat+0x48>
  1d:	mov    $0x132,%eax
  22:	call   *%gs:0x10
  29:	cmp    $0xfffff000,%eax
  2e:	ja     58 <fchmodat+0x58>
  30:	pop    %ebx
  31:	ret
  32:	lea    0x0(%esi),%esi
  38:	pop    %ebx
  39:	mov    $0xffffffea,%eax
  3e:	jmp    3f <fchmodat+0x3f>	3f: R_386_PC32	__syscall_error
  43:	nop
  44:	lea    0x0(%esi,%eiz,1),%esi
  48:	pop    %ebx
  49:	mov    $0xffffffa1,%eax
  4e:	jmp    4f <fchmodat+0x4f>	4f: R_386_PC32	__syscall_error
  53:	nop
  54:	lea    0x0(%esi,%eiz,1),%esi
  58:	pop    %ebx
  59:	jmp    5a <fchmodat+0x5a>	5a: R_386_PC32	__syscall_error

instead of

<fchmodat>:
   0:	sub    $0x8,%esp
   3:	mov    0x18(%esp),%eax
   7:	mov    %ebx,(%esp)
   a:	call   b <fchmodat+0xb>	b: R_386_PC32	__x86.get_pc_thunk.bx
   f:	add    $0x2,%ebx	11: R_386_GOTPC	_GLOBAL_OFFSET_TABLE_
  15:	mov    %edi,0x4(%esp)
  19:	test   $0xfffffeff,%eax
  1e:	jne    70 <fchmodat+0x70>
  20:	test   $0x1,%ah
  23:	jne    88 <fchmodat+0x88>
  25:	mov    0x14(%esp),%edx
  29:	mov    0x10(%esp),%ecx
  2d:	mov    0xc(%esp),%edi
  31:	xchg   %ebx,%edi
  33:	mov    $0x132,%eax
  38:	call   *%gs:0x10
  3f:	xchg   %edi,%ebx
  41:	cmp    $0xfffff000,%eax
  46:	ja     58 <fchmodat+0x58>
  48:	mov    (%esp),%ebx
  4b:	mov    0x4(%esp),%edi
  4f:	add    $0x8,%esp
  52:	ret
  53:	nop
  54:	lea    0x0(%esi,%eiz,1),%esi
  58:	mov    0x0(%ebx),%edx	5a: R_386_TLS_GOTIE	__libc_errno
  5e:	neg    %eax
  60:	mov    %eax,%gs:(%edx)
  63:	mov    $0xffffffff,%eax
  68:	jmp    48 <fchmodat+0x48>
  6a:	lea    0x0(%esi),%esi
  70:	mov    0x0(%ebx),%eax	72: R_386_TLS_GOTIE	__libc_errno
  76:	movl   $0x16,%gs:(%eax)
  7d:	mov    $0xffffffff,%eax
  82:	jmp    48 <fchmodat+0x48>
  84:	lea    0x0(%esi,%eiz,1),%esi
  88:	mov    0x0(%ebx),%eax	8a: R_386_TLS_GOTIE	__libc_errno
  8e:	movl   $0x5f,%gs:(%eax)
  95:	mov    $0xffffffff,%eax
  9a:	jmp    48 <fchmodat+0x48>

	* sysdeps/unix/sysdep.h (INLINE_SYSCALL_RETURN): New.
	(INLINE_SYSCALL_ERROR_RETURN): Likewise.
	* sysdeps/unix/sysv/linux/adjtime.c (ADJTIME): Use
	INLINE_SYSCALL_RETURN and INLINE_SYSCALL_ERROR_RETURN.
	* sysdeps/unix/sysv/linux/aio_sigqueue.c (__aio_sigqueue):
	Likewise.
	* sysdeps/unix/sysv/linux/dl-openat64.c (openat64): Likewise.
	* sysdeps/unix/sysv/linux/eventfd.c (eventfd): Likewise.
	* sysdeps/unix/sysv/linux/faccessat.c (faccessat): Likewise.
	* sysdeps/unix/sysv/linux/fchmodat.c (fchmodat): Likewise.
	* sysdeps/unix/sysv/linux/fcntl.c (do_fcntl): Likewise.
	* sysdeps/unix/sysv/linux/fstatfs64.c (__fstatfs64): Likewise.
	* sysdeps/unix/sysv/linux/ftruncate64.c (__ftruncate64): Likewise.
	* sysdeps/unix/sysv/linux/futimens.c (futimens): Likewise.
	* sysdeps/unix/sysv/linux/futimes.c (__futimes): Likewise.
	* sysdeps/unix/sysv/linux/futimesat.c (futimesat): Likewise.
	* sysdeps/unix/sysv/linux/fxstat.c (__fxstat): Likewise.
	* sysdeps/unix/sysv/linux/fxstat64.c (___fxstat64): Likewise.
	* sysdeps/unix/sysv/linux/fxstatat.c (__fxstatat): Likewise.
	* sysdeps/unix/sysv/linux/fxstatat64.c (__fxstatat64): Likewise.
	* sysdeps/unix/sysv/linux/gai_sigqueue.c (__gai_sigqueue):
	Likewise.
	* sysdeps/unix/sysv/linux/getpriority.c (__getpriority): Likewise.
	* sysdeps/unix/sysv/linux/getrlimit64.c (__getrlimit64): Likewise.
	* sysdeps/unix/sysv/linux/llseek.c (__llseek): Likewise.
	* sysdeps/unix/sysv/linux/lutimes.c (lutimes): Likewise.
	* sysdeps/unix/sysv/linux/lxstat.c (__lxstat): Likewise.
	* sysdeps/unix/sysv/linux/lxstat64.c (___lxstat64): Likewise.
	* sysdeps/unix/sysv/linux/mmap64.c (__mmap64): Likewise.
	* sysdeps/unix/sysv/linux/mq_close.c (mq_close): Likewise.
	* sysdeps/unix/sysv/linux/mq_open.c (__mq_open): Likewise.
	* sysdeps/unix/sysv/linux/mq_unlink.c (mq_unlink): Likewise.
	* sysdeps/unix/sysv/linux/msgget.c (msgget): Likewise.
	* sysdeps/unix/sysv/linux/prlimit.c (prlimit): Likewise.
	* sysdeps/unix/sysv/linux/pt-raise.c (raise): Likewise.
	* sysdeps/unix/sysv/linux/raise.c (raise): Likewise.
	* sysdeps/unix/sysv/linux/readahead.c (__readahead): Likewise.
	* sysdeps/unix/sysv/linux/reboot.c (reboot): Likewise.
	* sysdeps/unix/sysv/linux/semget.c (semget): Likewise.
	* sysdeps/unix/sysv/linux/semop.c (semop): Likewise.
	* sysdeps/unix/sysv/linux/semtimedop.c (semtimedop): Likewise.
	* sysdeps/unix/sysv/linux/setrlimit64.c (setrlimit64): Likewise.
	* sysdeps/unix/sysv/linux/shmat.c (shmat): Likewise.
	* sysdeps/unix/sysv/linux/shmdt.c (shmdt): Likewise.
	* sysdeps/unix/sysv/linux/shmget.c (shmget): Likewise.
	* sysdeps/unix/sysv/linux/signalfd.c (signalfd): Likewise.
	* sysdeps/unix/sysv/linux/sigpending.c (sigpending): Likewise.
	* sysdeps/unix/sysv/linux/sigprocmask.c ( __sigprocmask): Likewise.
	* sysdeps/unix/sysv/linux/sigqueue.c (__sigqueue): Likewise.
	* sysdeps/unix/sysv/linux/speed.c (cfsetospeed): Likewise.
	* sysdeps/unix/sysv/linux/statfs64.c (__statfs64): Likewise.
	* sysdeps/unix/sysv/linux/sysctl.c (__sysctl): Likewise.
	* sysdeps/unix/sysv/linux/tcsendbrk.c (tcsendbreak): Likewise.
	* sysdeps/unix/sysv/linux/tcsetattr.c (tcsetattr): Likewise.
	* sysdeps/unix/sysv/linux/timer_getoverr.c (timer_getoverrun):
	Likewise.
	* sysdeps/unix/sysv/linux/timer_gettime.c (timer_gettime):
	Likewise.
	* sysdeps/unix/sysv/linux/timer_settime.c (timer_settime):
	Likewise.
	* sysdeps/unix/sysv/linux/truncate64.c (truncate64): Likewise.
	* sysdeps/unix/sysv/linux/ustat.c (ustat): Likewise.
	* sysdeps/unix/sysv/linux/utimensat.c (utimensat): Likewise.
	* sysdeps/unix/sysv/linux/utimes.c (__utimes): Likewise.
	* sysdeps/unix/sysv/linux/xmknod.c (__xmknod): Likewise.
	* sysdeps/unix/sysv/linux/xmknodat.c (__xmknodat): Likewise.
	* sysdeps/unix/sysv/linux/xstat.c (__xstat): Likewise.
	* sysdeps/unix/sysv/linux/xstat64.c (___xstat64): Likewise.
	* sysdeps/unix/sysv/linux/xstatconv.c (__xstat_conv): Likewise.
	(__xstat64_conv): Likewise.
	(__xstat32_conv): Likewise.
	* sysdeps/unix/sysv/linux/sched_getaffinity.c
	(__sched_getaffinity_new): Add libc_hidden_proto and
	libc_hidden_def.  Use INLINE_SYSCALL_ERROR_RETURN.