AC: fix batch size settings (#3427)

Author: eaidova

tools/accuracy_checker/openvino/tools/accuracy_checker/launcher/input_feeder.py

@@ -405,7 +405,6 @@ def _parse_inputs_config(self, inputs_entry, default_layout='NCHW', precisions_l
                 inputs_entry, precision_info, not_config_inputs, precisions, layouts_info, layouts
             )
 
-
         return (
             constant_inputs,
             non_constant_inputs,

tools/accuracy_checker/openvino/tools/accuracy_checker/launcher/openvino_launcher.py

@@ -574,8 +574,11 @@ def _get_model_batch_size(self):
         input_info = input_nodes[0]
         layout = (
             self._process_layout(input_info.get_node().layout, input_info.get_node().friendly_name)
-            or self.default_layout
+            or ''
         )
+        input_shape = parse_partial_shape(input_info.partial_shape)
+        if not layout and len(input_shape) == len(self.default_layout):
+            layout = self.default_layout
         batch_pos = layout.find('N')
         if batch_pos != -1:
             return parse_partial_shape(input_info.partial_shape)[batch_pos]