Fix: [Win32] WIN32 may not be defined, always prefer the compiler predefined macro _WIN32

src/script/script_scanner.cpp

@@ -134,7 +134,7 @@ void ScriptScanner::RegisterScript(ScriptInfo *info)
 
 	if (this->info_list.find(script_name) != this->info_list.end()) {
 		/* This script was already registered */
-#ifdef WIN32
+#ifdef _WIN32
 		/* Windows doesn't care about the case */
 		if (strcasecmp(this->info_list[script_name]->GetMainScript(), info->GetMainScript()) == 0) {
 #else