mb/google/rex: Set display output type for eDP panel

Set the display type for the LCD panel configured via the gfx/generic
driver. This will ensure the correct DID/device address are generated
in the SSDT.

Change-Id: I8f390c58710c91bf77555f664e8f89f08ca59b30
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/80201
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
Reviewed-by: Subrata Banik <subratabanik@google.com>
diff --git a/src/mainboard/google/rex/variants/karis/overridetree.cb b/src/mainboard/google/rex/variants/karis/overridetree.cb
index fcff2c9..6cf286b 100644
--- a/src/mainboard/google/rex/variants/karis/overridetree.cb
+++ b/src/mainboard/google/rex/variants/karis/overridetree.cb
@@ -130,6 +130,7 @@
 				register "device_count" = "6"
 				# DDIA for eDP
 				register "device[0].name" = ""LCD""
+				register "device[0].type" = "panel"
 				# DDIB for HDMI
 				register "device[1].name" = ""DD01""
 				# TCP0 (DP-1) for port C0
diff --git a/src/mainboard/google/rex/variants/rex0/overridetree.cb b/src/mainboard/google/rex/variants/rex0/overridetree.cb
index 781fd59..46f86f1 100644
--- a/src/mainboard/google/rex/variants/rex0/overridetree.cb
+++ b/src/mainboard/google/rex/variants/rex0/overridetree.cb
@@ -155,6 +155,7 @@
 				register "device_count" = "6"
 				# DDIA for eDP
 				register "device[0].name" = ""LCD""
+				register "device[0].type" = "panel"
 				# DDIB for HDMI
 				# If HDMI is not enumerated in the kernel, then no GFX device should be added for DDIB
 				register "device[1].name" = ""DD01""