lib/resolve: drop a piece cycle-avoidance code

• It was too aggressive. Example I ran into: we have glue address in qry->ns but we want to find authoritative record by asking the NS.
• The anti-cycling measures are probably not perfect yet, but they seem to be fine enough and this commit seems very unlikely to make anything worse in practice.

• I still want to perform some particular experiments.

CI for the code change itself had been done on the tmp-issue-374 branch.

unmarked as a Work In Progress

added 3 commits

• 86540a4a...ad81423f - 2 commits from branch master
• 66b858c3 - lib/resolve: drop a piece cycle-avoidance code

Compare with previous version

merged

mentioned in commit 3a522fdf

mentioned in issue #374 (closed)