Merge branch 't1988-xml-wirelessmodem' into current
- t1988-xml-wirelessmodem: wwan: T1988: add ipv6 addressing nodes pppoe: T1318: add command to show statistics wwan: T1988: ppp: change order of debug and logfile options wwan: T1988: migrate operational mode commands wwan: T1988: support interface disable wwan: T1988: add support for Sierra Wireless MC7710 modem wwan: T1988: initial XML/Python representation