SDL: Fixed build after d0bbfdbfb881e5407911d84c12899bd5b442a130

From 42238f88eae1fb896ed459456cb574cc1ea4b706 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Thu, 1 Dec 2022 13:28:48 -0800
Subject: [PATCH] Fixed build after d0bbfdbfb881e5407911d84c12899bd5b442a130

---
 src/video/SDL_bmp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/video/SDL_bmp.c b/src/video/SDL_bmp.c
index be10432459e6..063f4875ae6a 100644
--- a/src/video/SDL_bmp.c
+++ b/src/video/SDL_bmp.c
@@ -697,8 +697,8 @@ int SDL_SaveBMP_RW(SDL_Surface *surface, SDL_RWops *dst, int freedst)
             } else {
                 SDL_InitFormat(&format, SDL_PIXELFORMAT_BGR24);
             }
-            surface = SDL_ConvertSurface(saveme, &format, 0);
-            if (surface == NULL) {
+            intermediate_surface = SDL_ConvertSurface(surface, &format, 0);
+            if (intermediate_surface == NULL) {
                 SDL_SetError("Couldn't convert image to %d bpp",
                              format.BitsPerPixel);
             }