Pointer as bool (libsdl-org#7214)

test/testiconv.c

@@ -61,7 +61,7 @@ int main(int argc, char *argv[])
 
     /* Initialize test framework */
     state = SDLTest_CommonCreateState(argv, 0);
-    if (state == NULL) {
+    if (!state) {
         return 1;
     }
 
@@ -90,7 +90,7 @@ int main(int argc, char *argv[])
 
     fname = GetResourceFilename(fname, "utf8.txt");
     file = fopen(fname, "rb");
-    if (file == NULL) {
+    if (!file) {
         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Unable to open %s\n", fname);
         return 1;
     }