Fix two problems:

Fix two problems:
1) if no default gateway is given the route command will fail
   and the script will abort with an error leading to an endless
   loop unless configuration is cancelled or changed. [1]
2) In the IPv6 case add -inet6 to not alter the legacy IP default
   route.

Reported by:	Oleg Ginzburg (olevole olevole.ru) [1]
Tested by:	Oleg Ginzburg (olevole olevole.ru) [1]
Approved by:	re (kib)