fix crash during torch model reload with inter op thread paramter set

torch allows setting the interop thread count only once
and before any inter-op parallel work is started because
it creates threadpool statically.
To follow this constraint, check the interop thread count
and set only if it's not yet set.

Author: snadampal

src/libtorch.cc

@@ -532,7 +532,9 @@ ModelState::ParseParameters()
         TRITONSERVER_ErrorDelete(err);
       }
     } else {
-      if (inter_op_thread_count > 0) {
+        if ((inter_op_thread_count > 0) &&
+             (inter_op_thread_count != at::get_num_interop_threads()) &&
+             (at::get_num_interop_threads() ==  std::thread::hardware_concurrency())) {
         at::set_num_interop_threads(inter_op_thread_count);
         LOG_MESSAGE(
             TRITONSERVER_LOG_INFO,