[roll] Roll fuchsia [kernel] Add power_state member to scheduler.

Some build updates required, and added two methods to the scheduler to
be called from a syscall context or dpc thread, in either case, from
thread context.

Acquire the lock, and call the power_state_ respective method.
+ Scheduler::SetPowerDomain
+ Scheduler::SetPowerLevel

Original-Bug: 330349572
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1135915
Original-Revision: 7b6a32e8798daa689e463869fa84f95dc267efe4
GitOrigin-RevId: 58bd85b5c9221be69808ae7a616f04e5c0c650a4
Change-Id: I06a0dca751b5954219e920d5893cfae38ea02027
diff --git a/stem b/stem
index 609ca91..d86b373 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="c14f3956c89ec2766e7752ebf5c9472b9869dff1"/>
+             revision="7b6a32e8798daa689e463869fa84f95dc267efe4"/>
   </projects>
   <hooks>
     <hook name="install-environment"