Update cmake for use with CentOS 8 rpms

* Update Findspdlog.cmake script to use spdlog's own cmake scripts
* Add linking to spdlog::spdlog to all deimos targets
* Clean up and update Findphobos.cmake
6 jobs for 110-update-for-rpms in 14 minutes and 31 seconds (queued for 3 minutes and 16 seconds)
Status Name Job ID Coverage
  Static Analysis
passed Format #5881
docker

00:00:53

passed Lint #5882
docker

00:05:24

 
  Build
passed Documentation #5883
docker

00:02:35

 
  Test
passed Authorisation Disabled #5885
docker

00:01:55

passed Default #5884
docker

00:01:57

passed centos7 #5886
docker

00:01:43