gma tgl: Add combo PHY programming sequence

This is required before any combo PHY ports can be used,  so it will be
performed early in the modeset.

Squashed clean-up:

  gma tgl: Refactor code for enhanced modularity

  This patch corrects code indentation and incorporates an internal
  procedure Propagate_To_Group for enhanced modularity. There are no
  changes to functionality.

  Signed-off-by: Dinesh Gehlot <digehlot@google.com>

Change-Id: Id0c2495872250e84057c3130cab19dea05a00b75
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-on: https://review.sourcearcade.org/c/libgfxinit/+/459
Tested-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/common/tigerlake/Makefile.inc b/common/tigerlake/Makefile.inc
index b99a57e..e9ed51f 100644
--- a/common/tigerlake/Makefile.inc
+++ b/common/tigerlake/Makefile.inc
@@ -1,3 +1,5 @@
+gfxinit-y += hw-gfx-gma-combo_phy.adb
+gfxinit-y += hw-gfx-gma-combo_phy.ads
 gfxinit-y += hw-gfx-gma-power_and_clocks.adb
 gfxinit-y += hw-gfx-gma-power_and_clocks.ads
 gfxinit-y += hw-gfx-gma-connectors.adb