Fix various tests/[frs]* files to be correct with 32 and 64-wide targets.

Still todo: tests/c*, tests/test-*

tests/switch-10.ispc

@@ -21,7 +21,7 @@ int switchit(int a, uniform int b) {
         }
         return -1234;
     }
-    case 32:
+    case 9999:
         *((int *)NULL) = 0;
     default:
         return 0;