SDL_mixer: cmake: Set required version to 3.1

SDL Commits
1 
From 63ee5cb8702e0c848e33f96c55aa732c345f96d5 Mon Sep 17 00:00:00 2001
From: Charlie Birks <[EMAIL REDACTED]>
Date: Sat, 6 Nov 2021 11:51:21 +0000
Subject: [PATCH] cmake: Set required version to 3.1

This is required for target_sources
---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9d3da96c..0048c7c2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.0.0)
+cmake_minimum_required(VERSION 3.1.0)
 project(SDL2_mixer C)
 
 # FIXME: CMAKE SUPPORT IN SDL2_mixer IS VERY INCOMPLETE YET !!!