mshv: Get the vmm capabilities offered by the hypervisor

mshv: Get the vmm capabilities offered by the hypervisor

Some hypervisor APIs are gated by feature bits in the
"vmm capabilities" partition property. Store the capabilities on
mshv_root module init, using HVCALL_GET_PARTITION_PROPERTY_EX.

This is not supported on all hypervisors. In that case, just set the
capabilities to 0 and proceed as normal.

Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com>
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com>
Reviewed-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>