Let remote RPCModule get function recursively (#11053)

Same reason as we changed the get_function to recursive searching. This is useful when we treat the local module as a data segment and wrap it in another empty LLVM module to reuse the export_lib API. After de-serialization in remote, the data segment will be translated as an imported module. Thus we need to fetch the function recursively.

src/runtime/rpc/rpc_module.cc

@@ -432,7 +432,7 @@ TVM_REGISTER_GLOBAL("runtime.RPCTimeEvaluator")
                 << "Cannot find " << f_preproc_name << " in the global function";
             f_preproc = *pf_preproc;
           }
-          PackedFunc pf = m.GetFunction(name, false);
+          PackedFunc pf = m.GetFunction(name, true);
           CHECK(pf != nullptr) << "Cannot find " << name << " in the global registry";
           return WrapTimeEvaluator(pf, dev, number, repeat, min_repeat_ms, f_preproc);
         }