Docker fix

Fix tags for armhf docker image reported in https://github.com/weetmuts/wmbusmeters/issues/762

.github/workflows/build_docker.yml

@@ -40,7 +40,7 @@ jobs:
         uses: docker/build-push-action@v3
         with:
           context: docker/
-          platforms: linux/amd64,linux/arm64,linux/armv7
+          platforms: linux/amd64,linux/arm64,linux/armhf
           push: true
           tags: weetmuts/wmbusmeters:latest
       -
@@ -49,7 +49,7 @@ jobs:
         uses: docker/build-push-action@v3
         with:
           context: docker/
-          platforms: linux/amd64,linux/arm64,linux/armv7
+          platforms: linux/amd64,linux/arm64,linux/armhf
           push: true
           tags: weetmuts/wmbusmeters:candidate-${{ fromJSON(steps.meta.outputs.json).labels['org.opencontainers.image.version'] }}
       -
@@ -58,6 +58,6 @@ jobs:
         uses: docker/build-push-action@v3
         with:
           context: docker/
-          platforms: linux/amd64,linux/arm64,linux/armv7
+          platforms: linux/amd64,linux/arm64,linux/armhf
           push: true
           tags: weetmuts/wmbusmeters:release-${{ fromJSON(steps.meta.outputs.json).labels['org.opencontainers.image.version'] }}

docker/Dockerfile

@@ -1,4 +1,4 @@
-FROM multiarch/alpine:${TARGETARCH}-latest-stable AS build
+FROM multiarch/alpine:${TARGETARCH}${TARGETVARIANT}-latest-stable AS build
 RUN apk add --no-cache alpine-sdk gcc linux-headers ncurses-dev librtlsdr-dev cmake libusb-dev bash
 RUN git clone https://github.com/weetmuts/wmbusmeters.git && \
     git clone https://github.com/weetmuts/rtl-wmbus.git && \
@@ -10,7 +10,7 @@ RUN make release && chmod 755 build/rtl_wmbus
 WORKDIR /rtl_433
 RUN mkdir build && cd build && cmake ../ && make
 
-FROM multiarch/alpine:${TARGETARCH}-latest-stable as scratch
+FROM multiarch/alpine:${TARGETARCH}${TARGETVARIANT}-latest-stable as scratch
 ENV QEMU_EXECVE=1
 RUN apk add --no-cache mosquitto-clients libstdc++ curl libusb ncurses rtl-sdr netcat-openbsd
 WORKDIR /wmbusmeters