gma: Split out config derivation and port probing

The GMA package has grown way too big. Move derivation of the internal
configuration into new package `Config_Helpers`, EDID probing into new
package `Display_Probing`.

Change-Id: Ib49ac7b00367be4295d18dba3afd1a0692e0497f
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/17757
Reviewed-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
diff --git a/common/Makefile.inc b/common/Makefile.inc
index 9745eb6..11215ee 100644
--- a/common/Makefile.inc
+++ b/common/Makefile.inc
@@ -7,9 +7,13 @@
 gfxinit-y += hw-gfx-dp_training.ads
 gfxinit-y += hw-gfx-edid.adb
 gfxinit-y += hw-gfx-edid.ads
+gfxinit-y += hw-gfx-gma-config_helpers.adb
+gfxinit-y += hw-gfx-gma-config_helpers.ads
 gfxinit-y += hw-gfx-gma-connector_info.adb
 gfxinit-y += hw-gfx-gma-connector_info.ads
 gfxinit-y += hw-gfx-gma-connectors.ads
+gfxinit-y += hw-gfx-gma-display_probing.adb
+gfxinit-y += hw-gfx-gma-display_probing.ads
 gfxinit-y += hw-gfx-gma-dp_aux_ch.ads
 gfxinit-y += hw-gfx-gma-dp_aux_request.adb
 gfxinit-y += hw-gfx-gma-dp_aux_request.ads