Always check for ENODATA with ENOATTR

Linux defines ENODATA and ENOATTR with the same value, which means that
code can miss on on the two without breaking.

FreeBSD does not have ENODATA and GlusterFS defines it as ENOATTR just
like Linux does.

On NetBSD, ENODATA != ENOATTR, hence we need to check for both values
to get portable behavior.

BUG: 764655
Change-Id: I003a3af055fdad285d235f2a0c192c9cce56fab8
Signed-off-by: Emmanuel Dreyfus <manu@netbsd.org>
Reviewed-on: http://review.gluster.org/8447
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>