Fix multi-platform images (#514)

.github/workflows/docker.yaml

@@ -0,0 +1,35 @@
+name: docker
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - .github/workflows/docker.yaml
+      - pkg/**
+      - go.*
+      - Dockerfile
+    tags:
+      - v*
+  pull_request:
+    branches:
+      - master
+    paths:
+      - .github/workflows/docker.yaml
+      - pkg/**
+      - go.*
+      - Dockerfile
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: docker/setup-qemu-action@v1
+      - uses: docker/setup-buildx-action@v1
+      - uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.CR_PAT }}
+      - run: make docker-build-push

.github/workflows/go.yaml

@@ -84,20 +84,6 @@ jobs:
           restore-keys: |
             go-${{ matrix.platform.GOOS }}-${{ matrix.platform.GOARCH }}-
       - run: make dist
-
-      # Docker image (Linux only)
-      - uses: docker/setup-buildx-action@v1
-        if: runner.os == 'Linux'
-      - uses: docker/login-action@v1
-        if: runner.os == 'Linux'
-        with:
-          registry: ghcr.io
-          username: ${{ github.repository_owner }}
-          password: ${{ secrets.CR_PAT }}
-      - run: make docker-build-push
-        if: runner.os == 'Linux'
-
-      # GitHub Releases
       - run: make dist-release
         if: startswith(github.ref, 'refs/tags/')
         env: