Check if there is a plugin socket first under `/run/docker/plugins/NAME.sock`.
If there is no socket for a plugin, check `/etc/docker/plugins/NAME.spec` and
`/usr/lib/docker/plugins/NAME.spec` for spec files.
Signed-off-by: David Calavera <david.calavera@gmail.com>
Upstream-commit: 6c0795747b00589641eb34eb7adce05a56d8840f
Component: engine