SDL: video: fix surface leak when duplicating mjpeg

SDL Commits
1 
From eb918af3dc9ca15071045cd2111b25fcbbe899a0 Mon Sep 17 00:00:00 2001
From: Green Sky <[EMAIL REDACTED]>
Date: Fri, 28 Mar 2025 21:02:13 +0100
Subject: [PATCH] video: fix surface leak when duplicating mjpeg

---
 src/video/SDL_surface.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/video/SDL_surface.c b/src/video/SDL_surface.c
index 4a616f9c9f6d4..c5291ade8b730 100644
--- a/src/video/SDL_surface.c
+++ b/src/video/SDL_surface.c
@@ -1948,6 +1948,7 @@ SDL_Surface *SDL_ConvertSurfaceAndColorspace(SDL_Surface *surface, SDL_PixelForm
             if (!convert->pixels) {
                 goto error;
             }
+            convert->flags &= ~SDL_SURFACE_PREALLOCATED;
             convert->pitch = surface->pitch;
             SDL_memcpy(convert->pixels, surface->pixels, size);