Changes to fix public MMS tests

If all this if-else branches are the same, except from the logResults: wouldn't be better if we just ommit them, and do only a single check like this one? 

if msg_type in ["sms", "mms", mmssub]:
     # Boilerplate code here
else:
            self.UTILS.reporting.logResult("info", "incorrect value received")
            self.UTILS.test.quitTest()