I was having issues with this install and found my solution here. https://www.cqrlog.com/node/2984
providing the symlink mentioned and compiling source from git repository worked for me.
I am now running latest CQRLOG on Ubuntu 21.04 with latest hamlib and Mariadb 10.5
I hope this will help others who may be having this issue
Ver 15.1 Distrib 10.5.10-MariaDB, for debian-linux-gnu (x86_64) using EditLine wrapper
rigctl Hamlib 4.2 Mon May 17 02:40:24 2021 +0000 SHA=cdad07
Cqrlog Ver:2.5.2 (001) Date:2021-07-12
VERSION="21.04 (Hirsute Hippo)"
Thank you OH1KH de Dave, N3MEQ