drm/xe/pf: Add functions to save and restore VF configuration blob

We already have support to save and restore GuC VF state, but that
will only work when the target VF configuration (provisioning) will
be exactly the same as the source VF configuration. To help with
assuring that both configurations match, allow to encode whole VF
configuration that can be saved as blob and restored later.

In the future we may want to use such captured configuration blobs
as templates to make sure we provision VFs with exactly the same
configuration that was previously tested or recommended, or when
debugfs knobs are not be available.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240919171528.1451-5-michal.wajdeczko@intel.com