Core: Fix some issues with various threading builds

src/core/log.c

@@ -12,7 +12,10 @@
 static struct mLogger* _defaultLogger = NULL;
 
 struct mLogger* mLogGetContext(void) {
-	struct mLogger* logger = mCoreThreadLogger();
+	struct mLogger* logger = NULL;
+#ifndef DISABLE_LOGGING
+	logger = mCoreThreadLogger();
+#endif
 	if (logger) {
 		return logger;
 	}

src/core/thread.c

@@ -367,6 +367,10 @@ struct mCoreThread* mCoreThreadGet(void) {
 	InitOnceExecuteOnce(&_contextOnce, _createTLS, NULL, 0);
 	return TlsGetValue(_contextKey);
 }
+#else
+struct mCoreThread* mCoreThreadGet(void) {
+	return NULL;
+}
 #endif
 
 #else