SDL: offscreen: Fix bogus surface pointer assignment

SDL Commits
1 
From 9ab140fad88f566fe840b9363cf0fa3dc2a3b23a Mon Sep 17 00:00:00 2001
From: Ethan Lee <[EMAIL REDACTED]>
Date: Wed, 28 Aug 2024 20:34:39 -0400
Subject: [PATCH] offscreen: Fix bogus surface pointer assignment

---
 src/video/offscreen/SDL_offscreenvulkan.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/video/offscreen/SDL_offscreenvulkan.c b/src/video/offscreen/SDL_offscreenvulkan.c
index 57c89d7ef57e8..901752cda6e12 100644
--- a/src/video/offscreen/SDL_offscreenvulkan.c
+++ b/src/video/offscreen/SDL_offscreenvulkan.c
@@ -220,7 +220,7 @@ bool OFFSCREEN_Vulkan_CreateSurface(SDL_VideoDevice *_this,
                                    const struct VkAllocationCallbacks *allocator,
                                    VkSurfaceKHR *surface)
 {
-    surface = NULL;
+    *surface = VK_NULL_HANDLE;
 
     if (!_this->vulkan_config.loader_handle) {
         return SDL_SetError("Vulkan is not loaded");