nointr.[ch] - don't inline funcs wrapping syscalls

nointr.[ch] - do not bother inlining funcs wrapping syscalls
remove _ALL_SOURCE define (AIX) where possible

remove _ALL_SOURCE define (AIX) where possible
_XOPEN_SOURCE >= 700 for *at() libc funcs

_XOPEN_SOURCE >= 700 for *at() libc funcs (openat, fstatat, etc)
(The Open Group Technical Standard, 2006, Extended API Set Part 2)
use Linux kernel user helper memory barrier on ARM