Remove the remaining uses of __inline in the XFS code base.

SGI-PV: 976035
SGI-Modid: xfs-linux-melb:xfs-kern:30774a
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>