xfs: fix uninitialized variable in _reflink_convert_cow

Fix an uninitialize variable.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 2f3d2d5..da6d08f 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -362,7 +362,7 @@
 	xfs_fileoff_t		end_fsb = XFS_B_TO_FSB(mp, offset + count);
 	xfs_extnum_t		idx;
 	bool			found;
-	int			error;
+	int			error = 0;
 
 	xfs_ilock(ip, XFS_ILOCK_EXCL);