Try and fix broken 32bit qemu builds on 64bit system

This patch adds a 'fix' for trying to build on armv7 32bit system
from a 64bit system.  qemu seems broken in this case.

.github/workflows/master-build.yml

@@ -56,6 +56,7 @@ jobs:
         file: ./Dockerfile-dev
         build-args: |
             BRANCH=${{ steps.branch-name.outputs.current_branch }}
+            BUILDX_QEMU_ENV=true
         push: true
         tags: |
           hemna6969/aprsd:${{ steps.branch-name.outputs.current_branch }}

.github/workflows/release_build.yml

@@ -39,10 +39,11 @@ jobs:
       uses: docker/build-push-action@v3
       with:
         context: "{{defaultContext}}:docker"
-        platforms: linux/amd64,linux/arm64
+        platforms: linux/amd64,linux/arm64,linux/arm/v7
         file: ./Dockerfile
         build-args: |
             VERSION=${{ inputs.aprsd_version }}
+            BUILDX_QEMU_ENV=true
         push: true
         tags: |
           hemna6969/aprsd:v${{ inputs.aprsd_version }}