!8614 remove context disable somas when variable_memory_max_size is set as somas feature switch

From: @laiyongqiang
Reviewed-by: @kisnwang,@jjfeing
Signed-off-by: @jjfeing

mindspore/ccsrc/runtime/device/kernel_runtime.cc

@@ -684,16 +684,13 @@ void KernelRuntime::AssignDynamicMemory(session::KernelGraph *graph) {
 
   if (is_enable_mem_reuse) {
     MS_LOG(INFO) << "Memory Reuse is enable...";
-    auto context = MsContext::GetInstance();
-    MS_EXCEPTION_IF_NULL(context);
-    auto variable_memory_max_size = context->get_param<std::string>(MS_CTX_VARIABLE_MEMORY_MAX_SIZE);
-    if (variable_memory_max_size == "0") {
-      mem_manager_->MallocSomasDynamicMem(graph);
-      mem_type = kSomasReuseDynamicMem;
-    } else {
-      mem_manager_->MallocReusedDynamicMem(graph);
-      mem_type = kReuseDynamicMem;
-    }
+#ifdef MEM_REUSE_DEBUG
+    mem_manager_->MallocReusedDynamicMem(graph);
+    mem_type = kReuseDynamicMem;
+#else
+    mem_manager_->MallocSomasDynamicMem(graph);
+    mem_type = kSomasReuseDynamicMem;
+#endif
   } else {
     MS_LOG(INFO) << "Memory Reuse is disable...";
   }