Allow interface type value none (sonic-net#1902)

This PR allow user to set none value to interface type. So there is a way to achieve the goal via CLI:

config interface type XXX none
config interface speed XXX 10000
config interface type XXX CR

scripts/portconfig

@@ -63,7 +63,7 @@ PORT_STATE_SUPPORTED_SPEEDS = "supported_speeds"
 VALID_INTERFACE_TYPE_SET = set(['CR','CR2','CR4','SR','SR2','SR4',
                                 'LR','LR4','KR','KR4','CAUI','GMII',
                                 'SFI','XLAUI','KR2','CAUI4','XAUI',
-                                'XFI','XGMII'])
+                                'XFI','XGMII', 'none'])
 
 class portconfig(object):
     """
@@ -166,7 +166,7 @@ class portconfig(object):
     def set_adv_interface_types(self, port, adv_interface_types):
         if self.verbose:
             print("Setting adv_interface_types %s on port %s" % (adv_interface_types, port))
-        
+
         if adv_interface_types != 'all':
             config_interface_type_list = [x.strip() for x in adv_interface_types.split(',')]
             config_interface_types = set(config_interface_type_list)
@@ -179,7 +179,7 @@ class portconfig(object):
                 print("Valid interface types:{}".format(','.join(VALID_INTERFACE_TYPE_SET)))
                 exit(1)
         self.db.mod_entry(PORT_TABLE_NAME, port, {PORT_ADV_INTERFACE_TYPES_CONFIG_FIELD_NAME: adv_interface_types})
-    
+
     def get_supported_speeds(self, port):
         if not self.namespace:
             state_db = SonicV2Connector(host="127.0.0.1")

tests/config_an_test.py

@@ -17,7 +17,7 @@
 @pytest.fixture(scope='module')
 def ctx(scope='module'):
     db = Db()
-    obj = {'config_db':db.cfgdb, 'namespace': ''}  
+    obj = {'config_db':db.cfgdb, 'namespace': ''}
     yield obj
 
 
@@ -56,6 +56,7 @@ def test_config_adv_speeds(self, ctx):
 
     def test_config_type(self, ctx):
         self.basic_check("type", ["Ethernet0", "CR4"], ctx)
+        self.basic_check("type", ["Ethernet0", "none"], ctx)
         self.basic_check("type", ["Invalid", "CR4"], ctx, operator.ne)
         self.basic_check("type", ["Ethernet0", ""], ctx, operator.ne)
         result = self.basic_check("type", ["Ethernet0", "Invalid"], ctx, operator.ne)