[MTD] generalise the handling of MTD-specific superblocks

Generalise the handling of MTD-specific superblocks so that JFFS2 and ROMFS
can both share it.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 095a9c9..151739a 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -937,6 +937,7 @@
 	struct list_head	s_files;
 
 	struct block_device	*s_bdev;
+	struct mtd_info		*s_mtd;
 	struct list_head	s_instances;
 	struct quota_info	s_dquot;	/* Diskquota specific options */