Drivers: hv: vmbus: Get rid of unnecessary state in hv_context

Currently we are replicating state in struct hv_context that is unnecessary -
this state can be retrieved from the hypervisor. Furthermore, this is a per-cpu
state that is being maintained as a global state in struct hv_context.
Get rid of this state in struct hv_context.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>