rename a structure

src/targets/gpu/device/include/migraphx/gpu/device/reduce.hpp

@@ -28,7 +28,7 @@ struct id
     }
 };
 
-struct scale
+struct mean
 {
     size_t item_num = 1;
     template <class T>

src/targets/gpu/device/reduce_mean.cpp

@@ -9,7 +9,7 @@ namespace device {
 void reduce_mean(hipStream_t stream, const argument& result, const argument& arg)
 {
     std::size_t item_num = arg.get_shape().elements() / result.get_shape().elements();
-    reduce(stream, result, arg, sum{}, 0, id{}, scale{item_num});
+    reduce(stream, result, arg, sum{}, 0, id{}, mean{item_num});
 }
 
 } // namespace device