rocr: make sure the member variable is conctructed (#1387)

Signed-off-by: Alex Xie <AlexBin.Xie@amd.com>

projects/rocr-runtime/runtime/hsa-runtime/core/runtime/amd_gpu_agent.cpp

@@ -496,6 +496,9 @@ void GpuAgent::InitScratchPool() {
 
   if (!core::Runtime::runtime_singleton_->flag().enable_scratch()) {
     scratch_pool_. ~SmallHeap();
+
+    // Reconstruct the object as default to allow ~GpuAgent to destruct the member variable
+    new (&scratch_pool_) SmallHeap();
     return;
   }