SWDEV-465602 - Fix random segfault

- Introduce a lock when checking isUserObjectValid. We need a lock
here as one can remove the userObject T2, leading to buffer overflow
when checking ranges in T1.

Change-Id: I058144b8cc463c90ab6bf5cf96bf937897742917

hipamd/src/hip_graph_internal.hpp

@@ -88,6 +88,7 @@ struct UserObject : public amd::ReferenceCountedObject {
   }
 
   static bool isUserObjvalid(UserObject* pUsertObj) {
+    amd::ScopedLock lock(UserObjectLock_);
     auto it = ObjectSet_.find(pUsertObj);
     if (it == ObjectSet_.end()) {
       return false;