Change linux faccessat syscall definition to match actual linux one.

[dchagin]

Summary

The AT_EACCESS and AT_SYMLINK_NOFOLLOW flags are actually implemented
within the glibc wrapper function for faccessat(). If either of these
flags are specified, then the wrapper function employs fstatat() to
determine access permissions.

[trasz]

sys/compat/linux/linux_file.c

601–602

Get rid of flag variable and pass AT_EACCESS directly, perhaps?

[dchagin]

whoops, yes, faccessat() as access() here use the real uid/gid.