[OV] remove workaround (#2262)

### Changes

Remove workaround for OV backend as the ticket was closed.

### Reason for changes

Code cleaning

### Related tickets

121115

### Tests

The current test validates this issue.
`test_if_model_fq_placement` in
`tests/openvino/native/quantization/test_graphs.py`

nncf/openvino/graph/model_transformer.py

@@ -567,5 +567,5 @@ def _apply_extract_if_body_transformation(
         name_to_node_mapping = OVModelTransformer._get_name_to_node_mapping(model)
         ov_node = name_to_node_mapping[transformation.if_node_name]
         if transformation.if_body_condition:
-            return ov.Model(ov_node.get_function(0))  # ticket: 121115
-        return ov.Model(ov_node.get_function(1))  # ticket: 121115
+            return ov_node.get_function(0)
+        return ov_node.get_function(1)