[roll] Roll fuchsia [intel-i915-tgl] Tiger Lake combo DDI PHY register definitions.

Intel's documentation is fairly minimal around these registers. For this
reason, we combined information from all the PRMs (DG1, Ice Lake) that
seem to cover the same combo PHY registers.

Original-Bug: 112730
Test: fx test intel-i915-tgl-test.cm
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/745444
Original-Revision: d8d3ae8a0d4fb3dd84a021fe91617dbfe9822a89
GitOrigin-RevId: 5c34d115f7c0331c05224a2ec3e963808a999dba
Change-Id: Iad962a7ab2f4618dd4793585e75e0130e539d90e
diff --git a/stem b/stem
index ddc2a9c..8486a3a 100644
--- a/stem
+++ b/stem
@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="fdee5acedade45a38476c8d25ceeb6073f1c4fb4"/>
+             revision="d8d3ae8a0d4fb3dd84a021fe91617dbfe9822a89"/>
   </projects>
   <hooks>
     <hook name="install-environment"