SDL_image: cmake: initialize SDLIMAGE_APNG_ENABLED unconditionally

SDL Commits
1 
From e34aec84d3627b88d05c666e35a5f855f6f9dab4 Mon Sep 17 00:00:00 2001
From: Stygian <[EMAIL REDACTED]>
Date: Sat, 12 Sep 2026 00:03:19 +0300
Subject: [PATCH] cmake: initialize SDLIMAGE_APNG_ENABLED unconditionally

When configured with -DSDLIMAGE_PNG=OFF -Wdev, an AUTHOR_WARNING is
triggered because SDLIMAGE_APNG_ENABLED was only set inside
if(SDLIMAGE_PNG).

Since APNG is unconditionally added to SDLIMAGE_BACKENDS, its enabled
variable must always be defined for the backend reporting loop.
---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6cc7ea147..9a12d0ceb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -844,8 +844,8 @@ endif()
 list(APPEND SDLIMAGE_BACKENDS PNG)
 list(APPEND SDLIMAGE_BACKENDS APNG)
 set(SDLIMAGE_PNG_ENABLED FALSE)
+set(SDLIMAGE_APNG_ENABLED FALSE)
 if(SDLIMAGE_PNG)
-    set(SDLIMAGE_APNG_ENABLED FALSE)
     set(SDLIMAGE_PNG_ENABLED TRUE)
     set(SDLIMAGE_LIBPNG_ENABLED FALSE)