ifupdown: iface: now trimming json values right after parsing

Ticket: None
Reviewed By: Roopa
Testing Done: smoke/testifupdown2.py:TestMakoJson

ifupdown2.TestMakoJson test was failing because the json values werent trimmed
Because of a trailing whitespace, a list of iface had an empty value, ifupdown2
was throwing an exception.

Signed-off-by: Julien Fortin <julien@cumulusnetworks.com>

ifupdown/iface.py

@@ -281,7 +281,7 @@ class ifaceJsonDecoder():
     @classmethod
     def json_to_ifaceobj(cls, ifaceattrdict):
         ifaceattrdict['config'] = OrderedDict([(k, (v if isinstance(v, list)
-                                                else [v]))
+                                                else [v.strip()]))
                                 for k,v in ifaceattrdict.get('config',
                                             OrderedDict()).items()])
         return iface(attrsdict=ifaceattrdict)