SDL_image: cmake: don't add private PNG include properties to SDL3_image (3ba07)

SDL Commits
1 
From 3ba077ecf9c835e9ab0c3246264f33b7becfea32 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Sun, 1 Feb 2026 20:49:56 +0100
Subject: [PATCH] cmake: don't add private PNG include properties to SDL3_image

The INTERFACE_SYSTEM_INCLUDE_DIRECTORIES property of PNG::PNG_shared might contain relative paths,
causing a CMake configure failure.

This is a bug in the PNG CMake scripts.

(manual backport of commit 8bab27f)

(cherry picked from commit dc6954a597588294badeea6d3f22cc11798e2437)
---
 CMakeLists.txt | 2 --
 1 file changed, 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ae80d88f..f9bd0145 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -671,9 +671,7 @@ if(SDL2IMAGE_PNG)
         if(SDL2IMAGE_PNG_ENABLED)
             if(SDL2IMAGE_PNG_SHARED)
                 target_include_directories(SDL2_image PRIVATE
-                    $<TARGET_PROPERTY:PNG::PNG,INCLUDE_DIRECTORIES>
                     $<TARGET_PROPERTY:PNG::PNG,INTERFACE_INCLUDE_DIRECTORIES>
-                    $<TARGET_PROPERTY:PNG::PNG,INTERFACE_SYSTEM_INCLUDE_DIRECTORIES>
                 )
                 target_get_dynamic_library(dynamic_png PNG::PNG)
                 message(STATUS "Dynamic libpng: ${dynamic_png}")