Check if the current builder supports multi-arch.

build/server-image/kube-apiserver/Dockerfile

@@ -14,14 +14,15 @@
 
 # This file create the kube-apiserver image.
 ARG BASEIMAGE
-
-FROM k8s.gcr.io/build-image/setcap:buster-v1.4.0
+# we use the hosts platform to apply the capabilities to avoid the need
+# to setup qemu for the builder.
+FROM --platform=linux/$BUILDARCH k8s.gcr.io/build-image/setcap:buster-v1.4.0
 ARG BINARY
 COPY ${BINARY} /${BINARY}
 # We apply cap_net_bind_service so that kube-apiserver can be run as
 # non-root and still listen on port less than 1024
 RUN setcap cap_net_bind_service=+ep /${BINARY}
 
-FROM ${BASEIMAGE}
+FROM --platform=linux/$TARGETARCH ${BASEIMAGE}
 ARG BINARY
 COPY --from=0 /${BINARY} /usr/local/bin/${BINARY}