[roll] Roll fuchsia [kernel][ktl] Include <compare> in <chrono> hack

The hackery used in ktl's <chrono> wrapper needs to be adjusted
whenever there's another libc++ header transitively used by some
ktl header that there wasn't before.  In C++20 mode, many things
use <compare>.

Original-Fixed: 91092
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/627661
Original-Revision: ac54e0406f98452fa5820660d53aadea7ab351e1
GitOrigin-RevId: 2b43eda2db18ab4397c3064434f79a6c95a3780d
Change-Id: I9326c33fbf11714d8c008bb25b87e82d9f24b2e4
diff --git a/stem b/stem
index a635fdc..bff9027 100644
--- a/stem
+++ b/stem
@@ -10,7 +10,7 @@
              githooks=""
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="e1081de52865c5b4dc6062f761e1f5b0b75d8978"/>
+             revision="ac54e0406f98452fa5820660d53aadea7ab351e1"/>
   </projects>
   <hooks>
     <hook name="install-environment"