sdl12-compat: include/SDL/SDL_events.h: fixed SDL_SysWMmsg redifinition error.

From 547c1b58c3a6210c2a7e5eeb84decf98d7723f24 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Mon, 28 Jun 2021 15:55:56 +0300
Subject: [PATCH] include/SDL/SDL_events.h: fixed SDL_SysWMmsg redifinition
 error.

---
 include/SDL/SDL_events.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/SDL/SDL_events.h b/include/SDL/SDL_events.h
index f48eb83..763d6a2 100644
--- a/include/SDL/SDL_events.h
+++ b/include/SDL/SDL_events.h
@@ -185,11 +185,11 @@ typedef struct SDL_UserEvent
     void *data2;
 } SDL_UserEvent;
 
-typedef struct SDL_SysWMmsg SDL_SysWMmsg;
+struct SDL_SysWMmsg;
 typedef struct SDL_SysWMEvent
 {
     Uint8 type;
-    SDL_SysWMmsg *msg;
+    struct SDL_SysWMmsg *msg;
 } SDL_SysWMEvent;
 
 typedef union SDL_Event