SubzeroReactor: Use new marl::Scheduler::Config API.

`marl::Scheduler::setWorkerThreadCount()` and `marl::Scheduler::setThreadInitializer()` have been deprecated.
`marl::Scheduler::Config` is the new API.

This got missed from 45493.

See https://github.com/google/marl/issues/139 for context.

Bug: b/140546382
Change-Id: Ic09c196b4c81f316cbf73de5395757108c16945c
diff --git a/src/Reactor/SubzeroReactor.cpp b/src/Reactor/SubzeroReactor.cpp
index 9b87a66..030dd43 100644
--- a/src/Reactor/SubzeroReactor.cpp
+++ b/src/Reactor/SubzeroReactor.cpp
@@ -244,9 +244,9 @@
 marl::Scheduler &getOrCreateScheduler()
 {
 	static auto scheduler = [] {
-		auto s = std::make_unique<marl::Scheduler>();
-		s->setWorkerThreadCount(8);
-		return s;
+		marl::Scheduler::Config cfg;
+		cfg.setWorkerThreadCount(8);
+		return std::make_unique<marl::Scheduler>(cfg);
 	}();
 
 	return *scheduler;