CMakeLists upgrade to 3.16 and cleanup

* Remove precompiled header hack
* Fixes for compilation on VS2022 Debug configurations

src/common/audio/music/music.cpp

@@ -38,6 +38,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdexcept>
+#include <memory>
 
 #include "i_sound.h"
 #include "i_music.h"

src/common/rendering/hwrenderer/postprocessing/hw_postprocessshader.h

@@ -1,5 +1,8 @@
 #pragma once
 
+#include "zstring.h"
+#include "tarray.h"
+
 enum class PostProcessUniformType
 {
 	Undefined,

src/common/thirdparty/richpresence.cpp

@@ -36,6 +36,7 @@
 */
 
 #include <time.h>
+#include <string.h>
 
 #include "common/engine/printf.h"
 #include "discord_rpc.h"