docker: enable docker.socket instead of docker.service
docker: enable docker.socket instead of docker.service

The docker daemon supports systemd socket activation. If we enable
docker.socket (and not docker.service) then the daemon will be started
when it is first used.

Signed-off-by: Dan Callaghan <41a685143d3b87a9b4bfaba76931643bdcd49cab@opengear.com>
Signed-off-by: Bruce Ashfield <284cc737d174a260eec2a2a6324a304f84b1ae0f@gmail.com>

lgirdk/meta-virtualization,lgirdk/meta-virtualization,lgirdk/meta-virtualization,lgirdk/meta-virtualization,lgirdk/meta-virtualization