remove more gcc 7 warnings

tinyldap.c

@@ -133,6 +133,7 @@ static void fixup(struct Filter* f) {
 	buffer_putsflush(buffer_2,"\"!\n");
       }
     }
+    /* fall through */
   case AND:
   case OR:
   case NOT:

tls_connect.c

@@ -117,6 +117,7 @@ alertfail:
     sc->message.l=7;
     r=tls_dowrite(fd,sc);
     if (r!=OK) return r;
+    /* fall through */
 
   default:
     sc->state=FAIL;