Merge pull request #3 from lexfrei/fix/arm64-support

fix: Use TARGETARCH for multi-platform builds

Author: lexfrei

Dockerfile

@@ -1,13 +1,16 @@
 ARG FROM=alpine
 FROM $FROM AS cni
-ARG GOARCH=amd64
+# TARGETARCH is automatically set by Docker buildx for multi-platform builds
+ARG TARGETARCH
+ARG GOARCH=${TARGETARCH:-amd64}
 ARG CNI_PLUGINS_VERSION=v1.1.1
 RUN apk add --no-cache curl && \
     curl -Lo cni.tar.gz https://github.com/containernetworking/plugins/releases/download/$CNI_PLUGINS_VERSION/cni-plugins-linux-$GOARCH-$CNI_PLUGINS_VERSION.tgz && \
     tar -xf cni.tar.gz
 
 FROM $FROM
-ARG GOARCH
+ARG TARGETARCH
+ARG GOARCH=${TARGETARCH:-amd64}
 ARG ALPINE_VERSION=v3.20
 LABEL maintainer="Cozystack <https://github.com/cozystack>"
 RUN echo -e "https://alpine.global.ssl.fastly.net/alpine/$ALPINE_VERSION/main\nhttps://alpine.global.ssl.fastly.net/alpine/$ALPINE_VERSION/community" > /etc/apk/repositories && \