!6460 delete bias from matmul

Merge pull request !6460 from chenzhongming/zomi_master

mindspore/ops/operations/math_ops.py

@@ -648,7 +648,7 @@ class MatMul(PrimitiveWithInfer):
             raise ValueError('MatMul input x, y should be the same dimension size and should be '
                              + f'equal to 2, while x size = {len(x)}, y size= {len(y)}')
 
-    def infer_shape(self, x, y, bias=None):
+    def infer_shape(self, x, y):
         self.check_shape_size(x, y)
         cls_name = self.name
         # expected dimension of x, y, x:[...,a,b] y:[..., c,d], the dim size should be the same except the last two
@@ -673,7 +673,7 @@ class MatMul(PrimitiveWithInfer):
         ret_dims = x[: -2] + [x_last[self.transpose_a], y_last[not self.transpose_b]]
         return ret_dims
 
-    def infer_dtype(self, x, y, bias=None):
+    def infer_dtype(self, x, y):
         args = {"x": x, "y": y}
         validator.check_tensor_type_same(args, mstype.float_type + mstype.int_type, self.name)
         if x.element_type() == mstype.int8: