SWDEV-455869 - Revert "SWDEV-410751 - Consider null amd::memory is invalid."

This reverts commit a9ff2c5a43.

Change-Id: I26c4b3c74b2861afc17f979492d025b59d4388ab

hipamd/src/hip_hmm.cpp

@@ -89,7 +89,7 @@ hipError_t hipMemPrefetchAsync(const void* dev_ptr, size_t count, int device,
   size_t offset = 0;
   amd::Memory* memObj = getMemoryObject(dev_ptr, offset);
 
-  if (memObj == nullptr || (memObj && count > (memObj->getSize() - offset))) {
+  if ((memObj != nullptr) && (count  > (memObj->getSize() - offset))) {
     HIP_RETURN(hipErrorInvalidValue);
   }
   if (device != hipCpuDeviceId && (static_cast<size_t>(device) >= g_devices.size())) {