RFR: Use ShenandoahAllocationThreshold in ShenandoahStaticHeuristics constructor

[Roman Kennke]

Aleksey pointed out this mistake:

diff --git
a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahStaticHeuristics.cpp
b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahStaticHeuristics.cpp
---
a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahStaticHeuristics.cpp
+++
b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahStaticHeuristics.cpp
@@ -34,7 +34,7 @@
   // Static heuristics may degrade to continuous if live data is larger
   // than free threshold. ShenandoahAllocationThreshold is supposed to
break this,
   // but it only works if it is non-zero.
-  SHENANDOAH_ERGO_OVERRIDE_DEFAULT(ShenandoahImmediateThreshold, 1);
+  SHENANDOAH_ERGO_OVERRIDE_DEFAULT(ShenandoahAllocationThreshold, 1);

   SHENANDOAH_ERGO_ENABLE_FLAG(ExplicitGCInvokesConcurrent);
   SHENANDOAH_ERGO_ENABLE_FLAG(ShenandoahImplicitGCInvokesConcurrent);

Ok?

Testing: tier3_gc_shenandoah

Roman