SDL: Just assert that RLE encoding isn't active

SDL Commits
1 
From ac0edbe9d28aa96cadd645736e5f26881982f11e Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Sat, 8 Nov 2025 13:44:38 -0800
Subject: [PATCH] Just assert that RLE encoding isn't active

We undo RLE encoding in the calling code, so we shouldn't need to do anything here.
---
 src/video/SDL_blit.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/video/SDL_blit.c b/src/video/SDL_blit.c
index ffe1ed3c4b405..66de5024ef405 100644
--- a/src/video/SDL_blit.c
+++ b/src/video/SDL_blit.c
@@ -198,12 +198,8 @@ bool SDL_CalculateBlit(SDL_Surface *surface, SDL_Surface *dst)
         return SDL_SetError("Blit combination not supported");
     }
 
-#ifdef SDL_HAVE_RLE
-    // Clean everything out to start
-    if (surface->internal_flags & SDL_INTERNAL_SURFACE_RLEACCEL) {
-        SDL_UnRLESurface(surface);
-    }
-#endif
+    // We should have cleared out RLE at this point
+    SDL_assert(!(surface->internal_flags & SDL_INTERNAL_SURFACE_RLEACCEL));
 
     map->blit = SDL_SoftBlit;
     map->info.src_surface = surface;