OS-2051 serial console login should set TERM appropriately

@@ -134,11 +134,11 @@
                 <propval name='modules' type='astring'
                         value='ldterm,ttcompat' />
                 <propval name='prompt' type='astring'
                         value='`uname -n` ttya login:' />
                 <propval name='terminal_type' type='astring'
-                        value='' />
+                        value='xterm' />
         </property_group>
 </instance>
 
 <instance name='ttyb' enabled='true'>
 

@@ -161,11 +161,11 @@
                 <propval name='modules' type='astring'
                         value='ldterm,ttcompat' />
                 <propval name='prompt' type='astring'
                         value='`uname -n` ttyb login:' />
                 <propval name='terminal_type' type='astring'
-                        value='' />
+                        value='xterm' />
         </property_group>
 </instance>
 
 <instance name='vt2' enabled='false'>