intel/gm45: native gfx init.

Tested on lenovo X200 in both text and gfx mode.

Change-Id: I273971d0f34ca3529959d4228e9516775459b806
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/6682
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>

src/mainboard/lenovo/x200/Kconfig

@@ -17,6 +17,8 @@ config BOARD_SPECIFIC_OPTIONS # dummy
 	select HAVE_OPTION_TABLE
 	select HAVE_CMOS_DEFAULT
 	select HAVE_ACPI_RESUME
+	select MAINBOARD_HAS_NATIVE_VGA_INIT
+	select MAINBOARD_HAS_NATIVE_VGA_INIT_TEXTMODECFG
 
 config MAINBOARD_DIR
 	string

src/mainboard/lenovo/x200/devicetree.cb

@@ -1,4 +1,10 @@
 chip northbridge/intel/gm45
+
+	register "gpu_use_spread_spectrum_clock" = "1"
+	register "gpu_lvds_dual_channel" = "0"
+	register "gpu_link_frequency_270_mhz" = "1"
+	register "gpu_lvds_num_lanes" = "4"
+
 	device cpu_cluster 0 on
 		chip cpu/intel/socket_BGA956
 			device lapic 0 on end