isofs: propagate umode_t

situation with mount options is the same as for udf

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index b71f631..7b99f5f 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -169,8 +169,8 @@
 	unsigned char map;
 	unsigned char check;
 	unsigned int blocksize;
-	mode_t fmode;
-	mode_t dmode;
+	umode_t fmode;
+	umode_t dmode;
 	gid_t gid;
 	uid_t uid;
 	char *iocharset;