Add early support for OSS.

examples/simple_playback.c

@@ -33,6 +33,7 @@ int main(int argc, char** argv)
     mal_context context;
     if (mal_context_init(NULL, 0, &context) != MAL_SUCCESS) {
         printf("Failed to initialize context.");
+		drwav_uninit(&wav);
         return -3;
     }
     
@@ -55,4 +56,4 @@ int main(int argc, char** argv)
     drwav_uninit(&wav);
     
     return 0;
-}
+}