fix make for a21, PIDs are always ints, linter things

kernel/user/app1/appl.cc

@@ -23,7 +23,7 @@ void Application::action() {  // NOLINT
 		// Make sure that we can use kout exclusively due to the hardware cursor
 		// otherwise we'd get a word jumble
 		koutsem.p(Guard::enter().vault());
-		kout.setPos(0U, id);
+		kout.setPos(0U, static_cast<unsigned>(id));
 		kout << i;
 		kout.flush();
 		koutsem.v(Guard::enter().vault());