Merge branch 'add_Maximum_tf' into 'master'

add Maximum in tensorflow_converter.py

See merge request !641

mace/python/tools/converter_tool/tensorflow_converter.py

@@ -55,6 +55,7 @@ TFSupportedOps = [
     'Div',
     'Min',
     'Max',
+    'Maximum',
     'Neg',
     'Abs',
     'Pow',
@@ -121,6 +122,7 @@ class TensorflowConverter(base_converter.ConverterInterface):
         TFOpType.Div.name: EltwiseType.DIV,
         TFOpType.Min.name: EltwiseType.MIN,
         TFOpType.Max.name: EltwiseType.MAX,
+        TFOpType.Maximum.name: EltwiseType.MAX,
         TFOpType.Neg.name: EltwiseType.NEG,
         TFOpType.Abs.name: EltwiseType.ABS,
         TFOpType.Pow.name: EltwiseType.POW,