tipc: Revert name table translation optimization

tipc: Revert name table translation optimization

Restores name table translation using a non-zero domain that is
"out of scope", which was broken by an earlier commit
(5d9c54c1e9ececcf7e99c4f014f9bec7ee3a7def). Comments have now been
added to the name table translation routine to make it clear that
there are actually three possible outcomes to a translation request
(found/not found/deferred), rather than just two (found/not found).

Note that a straightforward revert of the earlier commit is not
possible, as other changes to the name table translation logic
have occurred since the incorrect optimization was made.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>