libmsc/db.c: cosmetic: mark missing breaks in switch as intended

Change-Id: I3f4f34ecd0c5bb2d1a675ad5c4669fcffb87f292
Closes: Coverity CID#148209
diff --git a/src/libmsc/db.c b/src/libmsc/db.c
index d06db10..b5e7ad8 100644
--- a/src/libmsc/db.c
+++ b/src/libmsc/db.c
@@ -573,9 +573,11 @@
 	case 2:
 		if (update_db_revision_2())
 			goto error;
+	/* fall through */
 	case 3:
 		if (update_db_revision_3())
 			goto error;
+	/* fall through */
 	case 4:
 		if (update_db_revision_4())
 			goto error;