Revert "resolved: gracefully handle with packets with too large RR count"

This reverts commit fdfffdaf.

There are multiple reports that this breaks lookups for people, and reverting
this commit, even on the main branch (approx. v248-rc4), fixes the issue.

https://github.com/systemd/systemd/issues/18917#issuecomment-799421587
https://bodhi.fedoraproject.org/updates/FEDORA-2021-1c1a870ceb
(cherry picked from commit 7e88a9ae)