coreboot: add x230edp_12mb, remove x230fhd_12mb

New x230edp_12mb target uses the
https://review.coreboot.org/c/coreboot/+/28950 patchset to add an
X230_EDP target to the default coreboot branch.
Consequently the "fhd" coreboot branch is no longer needed and has
been safely removed.

resources/coreboot/default/patches/0016-lenovo-x230-fix-data.vbt-for-EDP.patch

@@ -0,0 +1,26 @@
+From 62cd7b24205122d366526aea1e3ad0c15ec8210f Mon Sep 17 00:00:00 2001
+From: Alexei Sorokin <sor.alexei@meowr.ru>
+Date: Sun, 27 Nov 2022 18:36:26 +0300
+Subject: [PATCH] lenovo/x230: fix the data.vbt path for the EDP variant
+
+---
+ src/mainboard/lenovo/x230/Kconfig | 3 ---
+ 1 file changed, 3 deletions(-)
+
+diff --git a/src/mainboard/lenovo/x230/Kconfig b/src/mainboard/lenovo/x230/Kconfig
+index b8cae24199..d72b6f8aea 100644
+--- a/src/mainboard/lenovo/x230/Kconfig
++++ b/src/mainboard/lenovo/x230/Kconfig
+@@ -62,9 +62,6 @@ config MAINBOARD_PART_NUMBER
+ config OVERRIDE_DEVICETREE
+ 	default "variants/\$(CONFIG_VARIANT_DIR)/overridetree.cb"
+ 
+-config INTEL_GMA_VBT_FILE
+-	default "variants/x230_edp/data.vbt" if BOARD_LENOVO_X230_EDP
+-
+ config USBDEBUG_HCD_INDEX
+ 	int
+ 	default 2
+-- 
+2.25.1
+