SDL: CI: Add Windows ARM64 builds

SDL Commits
1 
From 9170c0c7f8d3deebb60fff4a88e074de1c37a2f5 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <[EMAIL REDACTED]>
Date: Thu, 15 Jul 2021 18:35:20 -0500
Subject: [PATCH] CI: Add Windows ARM64 builds

---
 .github/workflows/main.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 97981b554..26bfc7060 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -9,8 +9,9 @@ jobs:
     strategy:
       matrix:
         platform:
-        - { name: Windows (x64), os: windows-latest }
+        - { name: Windows (x64), os: windows-latest, flags: -A x64 }
         - { name: Windows (x86), os: windows-latest, flags: -A Win32 }
+        - { name: Windows (ARM64), os: windows-latest, flags: -A ARM64 }
         - { name: Linux,   os: ubuntu-20.04, flags: -GNinja }
         - { name: MacOS,   os: macos-latest }
     steps: