drm/display: Add missing OLED Vesa brightnesses definitions

This commit adds missing luminance control registers to enable a more
standard way (VESA) to deal with eDP luminance control.

Cc: Anthony Koo <anthony.koo@amd.com>
Cc: Iswara Negulendran <iswara.nagulendran@amd.com>
Cc: Felipe Clark <felipe.clark@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230412000943.429031-1-Rodrigo.Siqueira@amd.com

include/drm/display/drm_dp.h

@@ -983,6 +983,7 @@
 
 #define DP_EDP_GENERAL_CAP_2		    0x703
 # define DP_EDP_OVERDRIVE_ENGINE_ENABLED		(1 << 0)
+# define DP_EDP_PANEL_LUMINANCE_CONTROL_CAPABLE		(1 << 4)
 
 #define DP_EDP_GENERAL_CAP_3		    0x704    /* eDP 1.4 */
 # define DP_EDP_X_REGION_CAP_MASK			(0xf << 0)
@@ -1008,6 +1009,7 @@
 # define DP_EDP_DYNAMIC_BACKLIGHT_ENABLE		(1 << 4)
 # define DP_EDP_REGIONAL_BACKLIGHT_ENABLE		(1 << 5)
 # define DP_EDP_UPDATE_REGION_BRIGHTNESS		(1 << 6) /* eDP 1.4 */
+# define DP_EDP_PANEL_LUMINANCE_CONTROL_ENABLE		(1 << 7)
 
 #define DP_EDP_BACKLIGHT_BRIGHTNESS_MSB     0x722
 #define DP_EDP_BACKLIGHT_BRIGHTNESS_LSB     0x723
@@ -1032,6 +1034,7 @@
 
 #define DP_EDP_DBC_MINIMUM_BRIGHTNESS_SET   0x732
 #define DP_EDP_DBC_MAXIMUM_BRIGHTNESS_SET   0x733
+#define DP_EDP_PANEL_TARGET_LUMINANCE_VALUE 0x734
 
 #define DP_EDP_REGIONAL_BACKLIGHT_BASE      0x740    /* eDP 1.4 */
 #define DP_EDP_REGIONAL_BACKLIGHT_0	    0x741    /* eDP 1.4 */