gma: Add GPU_Port types that are convenient for GMCH to use

Change-Id: I9120d084637d36a7e2276fcf3f630b3f7ed32509
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/25407
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/common/hw-gfx-gma-connector_info.adb b/common/hw-gfx-gma-connector_info.adb
index 798e61c..e8357be 100644
--- a/common/hw-gfx-gma-connector_info.adb
+++ b/common/hw-gfx-gma-connector_info.adb
@@ -87,7 +87,8 @@
    begin
       return
         (if Port_Cfg.Port = DIGI_A or
-            (Port_Cfg.Is_FDI and Port_Cfg.PCH_Port = PCH_LVDS)
+           (Port_Cfg.Is_FDI and Port_Cfg.PCH_Port = PCH_LVDS) or
+           Port_Cfg.Port = LVDS
          then 6
          else 8);
    end Default_BPC;