xfs: remove experimental tag for reflinks

But reject reflink + DAX file systems for now until the code to
support reflinks on DAX is actually implemented.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: port to 4.16]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/xfs/xfs_super.c

@@ -1668,7 +1668,7 @@ xfs_fs_fill_super(
 		}
 		if (xfs_sb_version_hasreflink(&mp->m_sb))
 			xfs_alert(mp,
-		"DAX and reflink have not been tested together!");
+		"DAX and reflink cannot be used together!");
 	}
 
 	if (mp->m_flags & XFS_MOUNT_DISCARD) {
@@ -1692,10 +1692,6 @@ xfs_fs_fill_super(
 	"EXPERIMENTAL reverse mapping btree feature enabled. Use at your own risk!");
 	}
 
-	if (xfs_sb_version_hasreflink(&mp->m_sb))
-		xfs_alert(mp,
-	"EXPERIMENTAL reflink feature enabled. Use at your own risk!");
-
 	error = xfs_mountfs(mp);
 	if (error)
 		goto out_filestream_unmount;