Fix build break - Hyperkube image needs kubelet/kubectl

`make quick-release-images KUBE_BUILD_CONFORMANCE=n` was broken since we
modified hyperkube to use actual binaries from a script. Temporarily
build the two additional binaries needed until we remove hyperkube image
completely. Added a TODO as a reminder

Author: dims

build/release-images.sh

@@ -30,6 +30,9 @@ if [[ "${KUBE_BUILD_CONFORMANCE}" =~ [yY] ]]; then
     CMD_TARGETS="${CMD_TARGETS} ${KUBE_CONFORMANCE_IMAGE_TARGETS[*]}"
 fi
 
+# TODO(dims): Remove this when we get rid of hyperkube image
+CMD_TARGETS="${CMD_TARGETS} cmd/kubelet cmd/kubectl"
+
 kube::build::verify_prereqs
 kube::build::build_image
 kube::build::run_build_command make all WHAT="${CMD_TARGETS}" KUBE_BUILD_PLATFORMS="${KUBE_SERVER_PLATFORMS[*]}"