Update OneHot to use v1 ops only (#4333)

Co-authored-by: Sang Ik Lee <sang.ik.lee@intel.com>

src/ngraph/frontend/onnx_import/op/onehot.cpp

@@ -18,9 +18,7 @@
 #include <memory>
 
 #include "default_opset.hpp"
-#include "ngraph/opsets/opset0.hpp"
 #include "onehot.hpp"
-#include "utils/common.hpp"
 #include "utils/reshape.hpp"
 
 namespace ngraph
@@ -38,13 +36,15 @@ namespace ngraph
                         std::make_shared<default_opset::Convert>(inputs.at(0), element::i64);
                     auto depth = reshape::interpret_as_scalar(inputs.at(1));
 
+                    // Rank 1 tensor containing exactly two elements: [off_value, on_value]
                     auto values = inputs.at(2);
-                    std::shared_ptr<ngraph::Node> off_value =
-                        reshape::interpret_as_scalar(std::make_shared<ngraph::opset0::Slice>(
-                            values, Coordinate{0}, Coordinate{1}));
-                    std::shared_ptr<ngraph::Node> on_value =
-                        reshape::interpret_as_scalar(std::make_shared<ngraph::opset0::Slice>(
-                            values, Coordinate{1}, Coordinate{2}));
+                    auto split_axis = default_opset::Constant::create(element::i64, {}, {0});
+                    auto off_on_values =
+                        std::make_shared<default_opset::Split>(values, split_axis, 2);
+                    auto off_value =
+                        reshape::interpret_as_scalar(get_output_element(off_on_values, 0ul));
+                    auto on_value =
+                        reshape::interpret_as_scalar(get_output_element(off_on_values, 1ul));
 
                     auto axis = node.get_attribute_value<std::int64_t>("axis", -1);