hppa: rewrite INLINE_SYSCALL

hppa: rewrite INLINE_SYSCALL

The semi-recent SYSCALL_CANCEL macro imposes a slight nuance on the
implementation of INLINE_SYSCALL: the nr argument cannot be expanded
directly but must be passed on to another macro which may expand it.
Most arches don't notice because INLINE_SYSCALL is defined in terms
of INTERNAL_SYSCALL which has the additional layer of expansion, but
on hppa, it was attempting to expand it directly.  That causes build
errors like so:
../sysdeps/unix/sysv/linux/sigsuspend.c: In function '__sigsuspend':
../sysdeps/unix/sysv/linux/sigsuspend.c:31:62: error:
	implicit declaration of function 'LOAD_ARGS___SYSCALL_NARGS'
../sysdeps/unix/sysv/linux/sigsuspend.c:31:304: error:
	called object 'LOAD_ARGS___SYSCALL_NARGS(set, 8)' is not a function

So rewrite hppa's INLINE_SYSCALL to use INTERNAL_SYSCALL like other
arches do.  This is also a nice clean up as the two macros had quite
a bit of duplicated logic.