mb/lenovo/t430: Enable libgfxinit

Enable libgfxinit.

Tested on Lenovo T430:
* LVDS
* VGA
* DP (using DP->HDMI adapter)

All three ports are working. The LVDS port is garbled under linux
when VGA or DP is connected, likely due to missing VBT.

Change-Id: I665661e93724072d1e8412cfcc0e818f824c8cb0
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/20117
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

src/mainboard/lenovo/t430/Kconfig

@@ -22,6 +22,8 @@ config BOARD_SPECIFIC_OPTIONS # dummy
 	select USE_NATIVE_RAMINIT
 	select ENABLE_VMX
 	select DRIVERS_LENOVO_HYBRID_GRAPHICS
+	select MAINBOARD_HAS_LIBGFXINIT
+	select GFX_GMA_INTERNAL_IS_LVDS
 
 config HAVE_IFD_BIN
 	bool

src/mainboard/lenovo/t430/Makefile.inc

@@ -2,3 +2,5 @@ romstage-y += romstage.c
 romstage-y += gpio.c
 ramstage-y += acpi_tables.c
 smm-y += smihandler.c
+
+ramstage-$(CONFIG_MAINBOARD_USE_LIBGFXINIT) += gma-mainboard.ads

src/mainboard/lenovo/t430/gma-mainboard.ads

@@ -0,0 +1,20 @@
+with HW.GFX.GMA;
+with HW.GFX.GMA.Display_Probing;
+
+use HW.GFX.GMA;
+use HW.GFX.GMA.Display_Probing;
+
+private package GMA.Mainboard is
+
+   ports : constant Port_List :=
+     (DP1,
+      DP2,
+      DP3,
+      HDMI1,
+      HDMI2,
+      HDMI3,
+      Analog,
+      Internal,
+      others => Disabled);
+
+end GMA.Mainboard;