SDL_image: Fix build when using both ImageIO and STB. Use first STB.

SDL Commits
1 
From 89c794e65ad90ada48242ace1f3fd94e6e3ab9a1 Mon Sep 17 00:00:00 2001
From: Sylvain Becker <[EMAIL REDACTED]>
Date: Thu, 24 Nov 2022 18:48:34 +0100
Subject: [PATCH] Fix build when using both ImageIO and STB. Use first STB.

---
 CMakeLists.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 802a79a6..73106751 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -307,10 +307,10 @@ if(APPLE)
             IMG_ImageIO.m
         )
 
-        if (SDL2IMAGE_PNG)
+        if (SDL2IMAGE_PNG AND NOT SDL2IMAGE_BACKEND_STB)
             target_compile_definitions(SDL2_image PRIVATE PNG_USES_IMAGEIO)
         endif()
-        if (SDL2IMAGE_JPG)
+        if (SDL2IMAGE_JPG AND NOT SDL2IMAGE_BACKEND_STB)
             target_compile_definitions(SDL2_image PRIVATE JPG_USES_IMAGEIO)
         endif()
     else()