Remove Dequantize Cast Optimizer MIN_FIRST limitation for spr-base (#940)

Signed-off-by: Lv, Liang1 <liang1.lv@intel.com>

Author: lvliang-intel

neural_compressor/adaptor/tf_utils/graph_rewriter/bf16/dequantize_cast_optimizer.py

@@ -56,8 +56,6 @@ def do_transformation(self):
 
             if len(dq_outputs) > 1:
                 continue
-            if dq_node.attr["mode"].s == b"MIN_FIRST":
-                continue
             cast_node = graph_info[i[1]].node
             cast_outputs = graph_info[i[1]].outputs
             all_cast_outputs_bf16 = True

test/tfnewapi/test_tensorflow_graph_dequantize_cast_optimizer_newapi.py

@@ -69,11 +69,12 @@ def test_dequantize_cast_min_first(self):
         graph_def = build_fake_graphdef(set_min_first=True)
         converted_graph_def = DequantizeCastOptimizer(graph_def).do_transformation()
         hasCast = False
+        # Remove MIN_FIRST limitation for spr-base, so the "Cast" will be removed now
         for i in converted_graph_def.node:
             if i.op == "Cast":
                 hasCast = True
                 break
-        self.assertEqual(hasCast, True)
+        self.assertEqual(hasCast, False)
 
     @disable_random()
     def test_dequantize_cast_multiple_outputs(self):