8257077: ZGC: Remove ZWorkers::run_serial()

Reviewed-by: stefank

Author: pliden

src/hotspot/share/gc/z/zWorkers.cpp

@@ -100,10 +100,6 @@ void ZWorkers::run(ZTask* task, uint nworkers) {
   _workers.run_task(task->gang_task());
 }
 
-void ZWorkers::run_serial(ZTask* task) {
-  run(task, 1  /* nworkers */);
-}
-
 void ZWorkers::run_parallel(ZTask* task) {
   run(task, nparallel());
 }

src/hotspot/share/gc/z/zWorkers.hpp

@@ -47,7 +47,6 @@ class ZWorkers {
 
   void set_boost(bool boost);
 
-  void run_serial(ZTask* task);
   void run_parallel(ZTask* task);
   void run_concurrent(ZTask* task);