[XFS] Cleanup some -Wundef flag warnings in the endian macros (thanks

Christoph).

SGI-PV: 942400
SGI-Modid: xfs-linux-melb:xfs-kern:23771a

Signed-off-by: Nathan Scott <nathans@sgi.com>

diff --cc fs/xfs/xfs_arch.h
Simple merge

diff --cc fs/xfs/xfs_bmap_btree.c
Simple merge

diff --cc fs/xfs/xfs_bmap_btree.h
Simple merge

diff --cc fs/xfs/xfs_dir_leaf.h
Simple merge

diff --cc fs/xfs/xfs_inode_item.c
Simple merge

diff --cc fs/xfs/xfs_log_priv.h
Simple merge