fix docker-proxy not statically linked

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

hack/make/binary-proxy

@@ -3,6 +3,8 @@
 set -e
 
 (
+	export CGO_ENABLED=0
+
 	GO_PACKAGE='github.com/docker/docker/cmd/docker-proxy'
 	BINARY_SHORT_NAME='docker-proxy'