SWDEV-382397 - Move VirtualGPU destruction back to the thread exit

OS can terminate unfinished queue thread from default stream at any
time. Potentially leaving the queue lock in a bad state and causing a
deadlock if runtime destroys VirtualGPU later from the host thread.

Change-Id: I247f102ee84e6b4dba947504933395071945c85d

rocclr/platform/commandqueue.cpp

@@ -66,6 +66,7 @@ bool HostQueue::terminate() {
       marker->awaitCompletion();
       marker->release();
     }
+    thread_.Release();
     thread_.acceptingCommands_ = false;
   } else {
     if (Os::isThreadAlive(thread_)) {