UBIFS: fill f_fsid

UBIFS stores 16-bit UUID in the superblock, and it is a good
idea to return part of it in 'f_fsid' filed of kstatfs structure.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

fs/ubifs/super.c

@@ -386,6 +386,7 @@ static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	buf->f_files = 0;
 	buf->f_ffree = 0;
 	buf->f_namelen = UBIFS_MAX_NLEN;
+	memcpy(&buf->f_fsid, c->uuid, sizeof(__kernel_fsid_t));
 
 	return 0;
 }