RDMA/vmw_pvrdma: Activate device on ethernet link up

Restore device state when ethernet link changes to active.

Acked-by: George Zhang <georgezhang@vmware.com>
Acked-by: Jorgen Hansen <jhansen@vmware.com>
Acked-by: Bryan Tan <bryantan@vmware.com>
Signed-off-by: Aditya Sarwade <asarwade@vmware.com>
Signed-off-by: Adit Ranadive <aditr@vmware.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>