SDL: Define _USE_MATH_DEFINES for Visual Studio (thanks @pionere!)

From c6e89619794ed6307f9efb0b242a2cdb605e1dc3 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Wed, 19 Oct 2022 08:05:47 -0700
Subject: [PATCH] Define _USE_MATH_DEFINES for Visual Studio (thanks @pionere!)

Fixes https://github.com/libsdl-org/SDL/issues/3790
---
 include/SDL_stdinc.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/SDL_stdinc.h b/include/SDL_stdinc.h
index c60d6eebb28d..06233c013fa0 100644
--- a/include/SDL_stdinc.h
+++ b/include/SDL_stdinc.h
@@ -80,9 +80,9 @@
 # include <ctype.h>
 #endif
 #ifdef HAVE_MATH_H
-# if defined(__WINRT__)
+# if defined(_MSC_VER)
 /* Defining _USE_MATH_DEFINES is required to get M_PI to be defined on
-   WinRT.  See http://msdn.microsoft.com/en-us/library/4hwaceh6.aspx
+   Visual Studio.  See http://msdn.microsoft.com/en-us/library/4hwaceh6.aspx
    for more information.
 */
 #  define _USE_MATH_DEFINES