drm/xe: stop including intel_display_{core, device}.h from xe_device_types.h

drm/xe: stop including intel_display_{core, device}.h from xe_device_types.h

Make xe->display pointer opaque to most of core xe driver. A few places
now need explicit include of intel_display_core.h.

With this dependency broken, changes in display should cause radically
less recompilation of xe.

Acked-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Link: https://lore.kernel.org/r/a12918f4d404e2d6d4e963126ce96df01d5064f3.1747907216.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>