drm/xe/pf: Add SR-IOV GuC Relay PF services

We already have mechanism that allows a VF driver to communicate
with the PF driver, now add PF side handlers for VF2PF requests
defined in version 1.0 of VF/PF GuC Relay ABI specification.

The VF2PF_HANDSHAKE request must be used by the VF driver to
negotiate the ABI version prior to sending any other request.
We will reset any negotiated version later during FLR.

The outcome of the VF2PF_QUERY_RUNTIME requests depends on actual
platform, for legacy platforms used as SDV is provided as-is, for
latest platforms it is preliminary, and might be changed.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240423180436.2089-5-michal.wajdeczko@intel.com