SDL: haiku: check if the returned _SDL_GLView is null or not

SDL Commits
1 
From 06eb10c51859cc51b9d20b3183d811ae5fd7f273 Mon Sep 17 00:00:00 2001
From: captain0xff <[EMAIL REDACTED]>
Date: Mon, 17 Feb 2025 01:17:13 +0530
Subject: [PATCH] haiku: check if the returned _SDL_GLView is null or not

---
 src/video/haiku/SDL_bvideo.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/video/haiku/SDL_bvideo.cc b/src/video/haiku/SDL_bvideo.cc
index a3bf1da74f6bd..ae37a733fb67b 100644
--- a/src/video/haiku/SDL_bvideo.cc
+++ b/src/video/haiku/SDL_bvideo.cc
@@ -241,6 +241,9 @@ static bool HAIKU_SetRelativeMouseMode(bool enabled)
 
 	SDL_BWin *bewin = _ToBeWin(window);
 	BGLView *_SDL_GLView = bewin->GetGLView();
+    if (_SDL_GLView == NULL) {
+        return false;
+    }
 
 	bewin->Lock();
 	if (enabled)