SDL: cmake: set SYSTEM property in SDL3Config.cmake for compatibility with older CMake versions

SDL Commits
1 
From 63cb5417975b0fa4f59c974c745e9fd71a1bf075 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Mon, 1 Apr 2024 20:09:51 +0200
Subject: [PATCH] cmake: set SYSTEM property in SDL3Config.cmake for
 compatibility with older CMake versions

---
 CMakeLists.txt            | 3 ---
 cmake/SDL3Config.cmake.in | 3 +++
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ff7c702f6aa63..4e7315be9f1af 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3212,9 +3212,6 @@ endif()
 add_library(SDL3_Headers INTERFACE)
 add_library(SDL3::Headers ALIAS SDL3_Headers)
 set_property(TARGET SDL3_Headers PROPERTY EXPORT_NAME "Headers")
-if(CMAKE_VERSION VERSION_GREATER_EQUAL "3.25")
-  set_property(TARGET SDL3_Headers PROPERTY EXPORT_NO_SYSTEM "TRUE")
-endif()
 target_include_directories(SDL3_Headers
   INTERFACE
     "$<BUILD_INTERFACE:${SDL3_BINARY_DIR}/include>"
diff --git a/cmake/SDL3Config.cmake.in b/cmake/SDL3Config.cmake.in
index 10f87283b6be8..e2ca50edcea6e 100644
--- a/cmake/SDL3Config.cmake.in
+++ b/cmake/SDL3Config.cmake.in
@@ -14,6 +14,9 @@ set(_sdl3_framework @SDL_FRAMEWORK@)
 # Find SDL3::Headers
 if(NOT TARGET SDL3::Headers)
   include("${CMAKE_CURRENT_LIST_DIR}/SDL3headersTargets.cmake")
+  if(NOT CMAKE_VERSION VERSION_LESS "3.25")
+    set_property(TARGET SDL3::Headers PROPERTY SYSTEM 0)
+  endif()
 endif()
 set(SDL3_Headers_FOUND TRUE)