Improve logging performance and make log priorities thread-safe

Fixes https://github.com/libsdl-org/SDL/issues/9679

test/testsensor.c

@@ -68,9 +68,6 @@ int main(int argc, char **argv)
         return 1;
     }
 
-    /* Enable standard application logging */
-    SDL_SetLogPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
-
     if (!SDLTest_CommonDefaultArgs(state, argc, argv)) {
         SDL_Quit();
         SDLTest_CommonDestroyState(state);