command: Add in support for IP address-based connections

This allows our users to set preferred-device to an IP address and bypass the
avahi discovery routines.

Change-Id: Ib17d1eac940ba4412c5a0a9889bb9f51540be368
diff --git a/mdt/command.py b/mdt/command.py
index 79064b4..698281e 100644
--- a/mdt/command.py
+++ b/mdt/command.py
@@ -15,6 +15,7 @@
 '''
 
 
+import re
 import os
 import socket
 
@@ -28,6 +29,9 @@
 from mdt import sshclient
 
 
+IP_ADDR_REGEX = re.compile('[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}')
+
+
 class NetworkCommand:
     def __init__(self):
         self.config = config.Config()
@@ -46,6 +50,9 @@
         if not self.preConnectRun(args):
             return 1
 
+        if self.device and IP_ADDR_REGEX.match(self.device):
+            self.address = self.device
+
         if not self.address:
             if self.device:
                 print('Waiting for device {0}...'.format(self.device))