SDL: SDL_cpuinfo: define __ARM_ARCH=8 for _M_ARM64

From b6e7c743db663713df85bdadc83dbcd9de61c274 Mon Sep 17 00:00:00 2001
From: Steven Noonan <[EMAIL REDACTED]>
Date: Thu, 25 Aug 2022 20:21:03 -0700
Subject: [PATCH] SDL_cpuinfo: define __ARM_ARCH=8 for _M_ARM64

Microsoft's compiler doesn't define __ARM_ARCH, but we have several
places that use it.
---
 include/SDL_cpuinfo.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/SDL_cpuinfo.h b/include/SDL_cpuinfo.h
index 43a8ac501756..b5ad0fcb8869 100644
--- a/include/SDL_cpuinfo.h
+++ b/include/SDL_cpuinfo.h
@@ -90,6 +90,7 @@ _m_prefetch(void *__P)
 #      include <arm64intr.h>
 #      include <arm64_neon.h>
 #      define __ARM_NEON 1 /* Set __ARM_NEON so that it can be used elsewhere, at compile time */
+#      define __ARM_ARCH 8
 #    endif
 #  endif
 #endif