hack: remove proxy.installer

It's no longer used

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

hack/dockerfile/install/proxy.installer

@@ -1,36 +0,0 @@
-#!/bin/sh
-
-# LIBNETWORK_COMMIT is used to build the docker-userland-proxy binary. When
-# updating the binary version, consider updating github.com/docker/libnetwork
-# in vendor.conf accordingly
-: "${LIBNETWORK_COMMIT:=64b7a4574d1426139437d20e81c0b6d391130ec8}"
-
-install_proxy() {
-	case "$1" in
-		"dynamic")
-			install_proxy_dynamic
-			return
-			;;
-		"")
-			export CGO_ENABLED=0
-			_install_proxy
-			;;
-		*)
-			echo 'Usage: $0 [dynamic]'
-			;;
-	esac
-}
-
-install_proxy_dynamic() {
-	export PROXY_LDFLAGS="-linkmode=external" install_proxy
-	export BUILD_MODE=${GO_BUILDMODE}
-	_install_proxy
-}
-
-_install_proxy() {
-	echo "Install docker-proxy version $LIBNETWORK_COMMIT"
-	git clone https://github.com/docker/libnetwork.git "$GOPATH/src/github.com/docker/libnetwork"
-	cd "$GOPATH/src/github.com/docker/libnetwork"
-	git checkout -q "$LIBNETWORK_COMMIT"
-	go build ${BUILD_MODE} -ldflags="$PROXY_LDFLAGS" -o ${PREFIX}/docker-proxy github.com/docker/libnetwork/cmd/proxy
-}