* Allocate min threads

(cherry picked from commit 6b36229d3c1e202665ca7b34d731194534fccdf9)

packages/fcl-base/src/fpthreadpool.pp

@@ -851,6 +851,8 @@ end;
 
 function TFPCustomSimpleThreadPool.AddTask(aTask: TThreadPoolTask): Boolean;
 begin
+  While ThreadCount<MinThreads do
+    FTaskList.AddThread;
   CheckQueuedTasks;
   Result:=DoAddTask(aTask);
   if (not Result) and QueueTasks then