Consolidate non cancellable openat call
This patch consolidates all the non cancellable openat{64} calls to use
the __openat{64}_nocancel identifier. For non cancellable targets it will
be just a macro to call the default respective symbol while on Linux
will be a internal one.
Checked on x86_64-linux-gnu, x86_64-linux-gnu-x32, and i686-linux-gnu.
* sysdeps/generic/not-cancel.h (openat_not_cancel): Remove macro.
(openat_not_cancel_3): Likewise.
(openat64_not_cancel_3): Likewise).
(openat_not_cancel_3): Likewise).
* sysdeps/unix/sysv/linux/not-cancel.h (openat_not_cancel): Remove
macro.
(openat_not_cancel_3): Likewise.
(openat64_not_cancel): Likewise.
(openat64_not_cancel_3): Likewise.
* sysdeps/unix/sysv/linux/openat.c (__openat_nocancel): New function.
* sysdeps/unix/sysv/linux/openat64.c (__openat64_nocancel): Likewise.
* io/ftw.c (open_dir_stream): Replace openat{64}_not_cancel{_3} with
__open{64}_nocancel.
* sysdeps/mach/hurd/opendir.c (__opendirat): Likewise.
* sysdeps/posix/getcwd.c (__getcwd): Likewise.
* sysdeps/posix/opendir.c (__opendirat): Likewise.