Pointer as bool (libsdl-org#7214)

test/testsem.c

@@ -261,7 +261,7 @@ int main(int argc, char **argv)
 
     /* Initialize test framework */
     state = SDLTest_CommonCreateState(argv, 0);
-    if (state == NULL) {
+    if (!state) {
         return 1;
     }