UBIFS: Change "ubifs mount" to "ubifsmount" in ubifsls output

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/common/cmd_ubifs.c b/common/cmd_ubifs.c
index 30b23d3..9526780 100644
--- a/common/cmd_ubifs.c
+++ b/common/cmd_ubifs.c
@@ -98,7 +98,7 @@
 	int ret;
 
 	if (!ubifs_mounted) {
-		printf("UBIFS not mounted, use ubifs mount to mount volume first!\n");
+		printf("UBIFS not mounted, use ubifsmount to mount volume first!\n");
 		return -1;
 	}