pkg/trim-after-delete: make docker socket path configurable
pkg/trim-after-delete: make docker socket path configurable

Docker Desktop proxies the docker socket at its default location
(/var/run/docker.sock), but allows connecting to the non-proxied
socket through /var/run/docker.sock.raw.

This patch allows the trim-after-delete utility to customize
the docker socket path, so that it can connect to the non-proxied
socket.

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>

furious-luke/linuxkit,JohnnyLeone/linuxkit,linuxkit/linuxkit,deitch/linuxkit,deitch/linuxkit,furious-luke/linuxkit,linuxkit/linuxkit,deitch/linuxkit,djs55/linuxkit,JohnnyLeone/linuxkit,deitch/linuxkit,furious-luke/linuxkit,linuxkit/linuxkit,furious-luke/linuxkit,djs55/linuxkit,linuxkit/linuxkit,JohnnyLeone/linuxkit,djs55/linuxkit,djs55/linuxkit,djs55/linuxkit,linuxkit/linuxkit,JohnnyLeone/linuxkit,JohnnyLeone/linuxkit,deitch/linuxkit,furious-luke/linuxkit