[XFS] remove INT_GET and friends

Thanks to hch's endian work, INT_GET etc are no longer used, and may as
well be removed. INT_SET is still used in the acl code, though.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31756a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>