net/vmnet: implement shared mode (vmnet-shared)

net/vmnet: implement shared mode (vmnet-shared)

Interaction with vmnet.framework in different modes
differs only on configuration stage, so we can create
common `send`, `receive`, etc. procedures and reuse them.

Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Tested-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Signed-off-by: Phillip Tennen <phillip@axleos.com>
Signed-off-by: Vladislav Yaroshchuk <Vladislav.Yaroshchuk@jetbrains.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>