Add multi-arch builds

.github/workflows/main.yml

@@ -68,6 +68,9 @@ jobs:
         VER=$(cat VERSION)
         echo "VERSION=$VER" >> $GITHUB_ENV
 
+    - name: Set up QEMU
+      uses: docker/setup-qemu-action@v1
+
     - name: Set up Docker Buildx
       uses: docker/setup-buildx-action@v1
 
@@ -84,6 +87,7 @@ jobs:
         push: true
         context: .
         file: Dockerfile
+        platforms: linux/amd64,linux/arm64,linux/arm/v7
         tags: |
           ${{ env.USER }}/${{ env.REPO }}:${{ env.VERSION }}
           ${{ env.USER }}/${{ env.REPO }}:latest