drivers/intel/gma: Add textmode support with libgfxinit

Add an alternative gfxinit implementation for textmode. The legacy VGA
plane and textmode is configured through coreboot provided functions.
libgfxinit uses this plane as alternative to the usual high resolution
plane.

Change-Id: Iad0754c50fc6faec35f49583fe1c7cb50ac6c0c5
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: https://review.coreboot.org/17279
Tested-by: build bot (Jenkins)
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/device/Kconfig b/src/device/Kconfig
index d238547..c90da89 100644
--- a/src/device/Kconfig
+++ b/src/device/Kconfig
@@ -53,6 +53,7 @@
 	bool "Use libgfxinit for native graphics initialization"
 	depends on MAINBOARD_DO_NATIVE_VGA_INIT
 	depends on MAINBOARD_HAS_LIBGFXINIT
+	select MAINBOARD_HAS_NATIVE_VGA_INIT_TEXTMODECFG
 	select RAMSTAGE_LIBHWBASE
 	default n
 	help