drm/i915/lnl: Add display definitions

Add Lunar Lake platform definitions for i915 display. The support for
LNL will be added to the xe driver, with i915 only driving the display
side. Xe2 display is derived from the Xe_LPD+ IP; additional feature
deltas will be introduced in subsequent patches, so here it's just
adding a separate xe2_lpd_display struct.

v2: Use a LPDP_FEATURES macro (Matt Roper)
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230919192128.2045154-2-lucas.demarchi@intel.com

drivers/gpu/drm/i915/display/intel_display_device.c

@@ -759,6 +759,10 @@ static const struct intel_display_device_info xe_lpdp_display = {
 	XE_LPDP_FEATURES,
 };
 
+static const struct intel_display_device_info xe2_lpd_display = {
+	XE_LPDP_FEATURES,
+};
+
 /*
  * Separate detection for no display cases to keep the display id array simple.
  *
@@ -838,6 +842,7 @@ static const struct {
 	const struct intel_display_device_info *display;
 } gmdid_display_map[] = {
 	{ 14,  0, &xe_lpdp_display },
+	{ 20,  0, &xe2_lpd_display },
 };
 
 static const struct intel_display_device_info *