SWDEV-496106 - Use lock_ops to avoid race condition in safe_stream.

Change-Id: I5e98c34a41434e2f7d2e6406ea30ddcf01b1091c

hipamd/src/hip_mempool_impl.hpp

@@ -261,6 +261,7 @@ class MemoryPool : public amd::ReferenceCountedObject {
 
   /// Add a safe stream for quick looks-ups if event dependencies option is enabled
   void AddSafeStream(Stream* event_stream, Stream* wait_stream) {
+    amd::ScopedLock lock(lock_pool_ops_);
     if (EventDependencies()) {
       free_heap_.AddSafeStream(event_stream, wait_stream);
     }