SDL: Support PNG icons in the SDL test code

SDL Commits
1 
From 56269cd0100a0073c4b892bba380f651ea096557 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Mon, 24 Nov 2025 13:16:00 -0800
Subject: [PATCH] Support PNG icons in the SDL test code

---
 src/test/SDL_test_common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/test/SDL_test_common.c b/src/test/SDL_test_common.c
index 7bce2eeb7f793..aab79b300ac5b 100644
--- a/src/test/SDL_test_common.c
+++ b/src/test/SDL_test_common.c
@@ -1143,7 +1143,7 @@ static SDL_Surface *SDLTest_LoadIcon(const char *file)
     SDL_Surface *icon;
 
     /* Load the icon surface */
-    icon = SDL_LoadBMP(file);
+    icon = SDL_LoadSurface(file);
     if (!icon) {
         SDL_Log("Couldn't load %s: %s", file, SDL_GetError());
         return NULL;