[XFS] Sync up kernel and user-space headers

SGI-PV: 986558

SGI-Modid: xfs-linux-melb:xfs-kern:32231a

Signed-off-by: Barry Naujok <bnaujok@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff --git a/fs/xfs/xfs_bit.h b/fs/xfs/xfs_bit.h
index 8e0e463..bca7b24 100644
--- a/fs/xfs/xfs_bit.h
+++ b/fs/xfs/xfs_bit.h
@@ -61,8 +61,7 @@
 /* Get low bit set out of 32-bit argument, -1 if none set */
 static inline int xfs_lowbit32(__uint32_t v)
 {
-	unsigned long	t = v;
-	return (v) ? find_first_bit(&t, 32) : -1;
+	return ffs(v) - 1;
 }
 
 /* Get low bit set out of 64-bit argument, -1 if none set */