drm/xe/display: Xe stolen memory handling for fbc support

drm/xe/display: Xe stolen memory handling for fbc support

Add Xe stolen memory handling for fbc.

v3:
  - v2: Add parenthesis around parameter in i915_gem_stolen_node_allocated
v2:
  - define i915_gem_stolen_area_address/size as !WARN_ON(1)
  - squash common type addition into this patch

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>