Base interface inlining determination directly on VM startup phase

The JIT can re-enter STARTUP_STATE after leaving it, and it can remain
in that state for much longer than one might naively expect, inhibiting
these heuristics.

runtime/compiler/optimizer/J9Inliner.cpp

@@ -840,7 +840,7 @@ bool TR_J9InterfaceCallSite::findCallSiteTargetImpl(TR_CallStack *callStack, TR_
          // won't be extended later.
          bool useVftTestHeuristics = true;
          TR::PersistentInfo *persistInfo = comp()->getPersistentInfo();
-         if (persistInfo->getJitState() == STARTUP_STATE)
+         if (TR::Compiler->vm.isVMInStartupPhase(comp()->fej9()->getJ9JITConfig()))
             {
             const static bool useVftTestHeuristicsDuringStartup =
                feGetEnv("TR_useInterfaceVftTestHeuristicsDuringStartup") != NULL;