chore: build talosctl for Darwin / Apple Silicon

This adds a new target `darwin/arm64` which is supported since Go 1.16.

Signed-off-by: Andrey Smirnov <smirnov.andrey@gmail.com>

.drone.jsonnet

@@ -551,6 +551,7 @@ local release = {
       '_out/talosctl-cni-bundle-amd64.tar.gz',
       '_out/talosctl-cni-bundle-arm64.tar.gz',
       '_out/talosctl-darwin-amd64',
+      '_out/talosctl-darwin-arm64',
       '_out/talosctl-linux-amd64',
       '_out/talosctl-linux-arm64',
       '_out/talosctl-linux-armv7',

Dockerfile

@@ -214,15 +214,23 @@ LABEL "alpha.talos.dev/version"="${VERSION}"
 LABEL org.opencontainers.image.source https://github.com/talos-systems/talos
 ENTRYPOINT ["/talosctl"]
 
-FROM base AS talosctl-darwin-build
+FROM base AS talosctl-darwin-amd64-build
 WORKDIR /src/cmd/talosctl
 ARG GO_BUILDFLAGS
 ARG GO_LDFLAGS
 RUN --mount=type=cache,target=/.cache GOOS=darwin GOARCH=amd64 go build ${GO_BUILDFLAGS} -ldflags "${GO_LDFLAGS}" -o /talosctl-darwin-amd64
 RUN chmod +x /talosctl-darwin-amd64
 
+FROM base AS talosctl-darwin-arm64-build
+WORKDIR /src/cmd/talosctl
+ARG GO_BUILDFLAGS
+ARG GO_LDFLAGS
+RUN --mount=type=cache,target=/.cache GOOS=darwin GOARCH=arm64 go build ${GO_BUILDFLAGS} -ldflags "${GO_LDFLAGS}" -o /talosctl-darwin-arm64
+RUN chmod +x /talosctl-darwin-arm64
+
 FROM scratch AS talosctl-darwin
-COPY --from=talosctl-darwin-build /talosctl-darwin-amd64 /talosctl-darwin-amd64
+COPY --from=talosctl-darwin-amd64-build /talosctl-darwin-amd64 /talosctl-darwin-amd64
+COPY --from=talosctl-darwin-arm64-build /talosctl-darwin-arm64 /talosctl-darwin-arm64
 
 # The kernel target is the linux kernel.