drm/i915/gvt: Initialize MMIO Block with HW state

MMIO block with tracked mmio, is introduced for the sake of performance
of searching tracked mmio. All the tracked mmio needs to get the initial
value from the HW state during vGPU being created. This patch is to
initialize the tracked registers in MMIO block with the HW state.

v2: Add "Fixes:" line for this patch (Zhenyu)

Fixes: 65f9f6fe ("drm/i915/gvt: Optimize MMIO register handling for some large MMIO blocks")
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>