Return just the effective permissions, and forget about the mask.  It isn't
worth the complexity.

WARNING: This breaks backwards compatibility with overly-picky nfsv4->posix
acl translation, as may has been included in some patched versions of libacl.
To our knowledge no such version was every distributed by anyone outside citi.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>