gma: Add G45 support

The following ports are implemented: HDMI/DVI, VGA, LVDS and DP.

Tested with gfx_test and coreboot on a Thinkpad X200 (GM45).

Change-Id: Ifc05a1516329a61772af84558e5bfceb4d4ca277
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/21295
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: Nico Huber <nico.h@gmx.de>
diff --git a/configs/g45 b/configs/g45
new file mode 100644
index 0000000..6b54563
--- /dev/null
+++ b/configs/g45
@@ -0,0 +1,5 @@
+CONFIG_GFX_GMA_CPU		= G45
+CONFIG_GFX_GMA_CPU_VARIANT	= Normal
+CONFIG_GFX_GMA_INTERNAL_PORT	= LVDS
+CONFIG_GFX_GMA_ANALOG_I2C_PORT	= PCH_DAC
+CONFIG_GFX_GMA_DEFAULT_MMIO	= 16\#e000_0000\#