Refs #100852  Replacing usage of "ccndc srv" with a simple dig-based lookup

The main reason for replacement is that it is necessary to remember
auto-configured route and it is impossible to do so with just "ccndc srv"
(unless it is modified appropriately).

The consequence of not remembering is a potential infinite loop within
ccnd-autoconfig script.
Merge branch '100852-local-ccnd-autoconfig'