libxfs: fix xfs_trans_alloc_empty namespace

Do all the right libxfs_ magic for this new function.

Reported-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
diff --git a/include/xfs_trans.h b/include/xfs_trans.h
index d9f9ec8..17d286a 100644
--- a/include/xfs_trans.h
+++ b/include/xfs_trans.h
@@ -90,7 +90,7 @@
 int	libxfs_trans_alloc(struct xfs_mount *mp, struct xfs_trans_res *resp,
 			   uint blocks, uint rtextents, uint flags,
 			   struct xfs_trans **tpp);
-int	xfs_trans_alloc_empty(struct xfs_mount *mp, struct xfs_trans **tpp);
+int	libxfs_trans_alloc_empty(struct xfs_mount *mp, struct xfs_trans **tpp);
 int	libxfs_trans_commit(struct xfs_trans *);
 void	libxfs_trans_cancel(struct xfs_trans *);
 struct xfs_buf *libxfs_trans_getsb(struct xfs_trans *, struct xfs_mount *, int);
diff --git a/libxfs/trans.c b/libxfs/trans.c
index 229fe56..e161c28 100644
--- a/libxfs/trans.c
+++ b/libxfs/trans.c
@@ -206,7 +206,7 @@
  * without any dirty data.
  */
 int
-xfs_trans_alloc_empty(
+libxfs_trans_alloc_empty(
 	struct xfs_mount		*mp,
 	struct xfs_trans		**tpp)
 {