What should I do with "No candidate ver" packages when upgrading Ubuntu?

Upgrading a server from 18.04 to 20.04 I get a list of No candidate ver packages. What do I do with this list? Should they be removed and cleaned up?

I know I don't need older version of the PHP packages, for example, but if I'm presented with things like systemd-services which I don't know about, how do I check if these are required and safely remove them if necessary?

Ignoring this warning doesn't prevent the upgrade from completing.

No candidate ver:  libxcb-util0
No candidate ver:  libxmlada4.1
No candidate ver:  libxmlada4.4.0
No candidate ver:  libxp6
No candidate ver:  libxtables10
No candidate ver:  libyahoo2-11
No candidate ver:  libzeroc-ice35
No candidate ver:  linux-image-3.13.0-123-generic
No candidate ver:  linux-image-3.13.0-48-generic
No candidate ver:  linux-image-3.13.0-68-generic
No candidate ver:  linux-image-4.4.0-121-generic
No candidate ver:  linux-image-4.4.0-140-generic
No candidate ver:  linux-image-4.4.0-178-generic
No candidate ver:  linux-image-4.4.0-185-generic
No candidate ver:  linux-image-4.4.0-83-generic
No candidate ver:  linux-image-extra-4.4.0-121-generic
No candidate ver:  linux-image-extra-4.4.0-140-generic
No candidate ver:  linux-image-extra-4.4.0-83-generic
No candidate ver:  linux-modules-4.4.0-178-generic
No candidate ver:  linux-modules-4.4.0-185-generic
No candidate ver:  linux-modules-extra-4.4.0-178-generic
No candidate ver:  linux-modules-extra-4.4.0-185-generic
No candidate ver:  lxc-common
No candidate ver:  mountall
No candidate ver:  mysql-server-5.5
No candidate ver:  perl-modules
No candidate ver:  php5-cli
No candidate ver:  php5-common
No candidate ver:  php5-curl
No candidate ver:  php5-gd
No candidate ver:  php5-intl
No candidate ver:  php5-json
No candidate ver:  php5-mcrypt
No candidate ver:  php5-mysql
No candidate ver:  php5-readline
No candidate ver:  php7.0-bz2
No candidate ver:  php7.0-cli
No candidate ver:  php7.0-common
No candidate ver:  php7.0-curl
No candidate ver:  php7.0-gd
No candidate ver:  php7.0-intl
No candidate ver:  php7.0-json
No candidate ver:  php7.0-mbstring
No candidate ver:  php7.0-mcrypt
No candidate ver:  php7.0-mysql
No candidate ver:  php7.0-opcache
No candidate ver:  php7.0-readline
No candidate ver:  php7.0-xml
No candidate ver:  php7.0-zip
No candidate ver:  python3-aptdaemon.pkcompat
No candidate ver:  python3.4
No candidate ver:  python3.4-minimal
No candidate ver:  python3.5-minimal
No candidate ver:  ruby1.9.1
No candidate ver:  systemd-services
No candidate ver:  systemd-shim
No candidate ver:  sysv-rc
No candidate ver:  upstart
No candidate ver:  webmin

As mentioned in the comments, this was originally an Ubuntu 14.04 server as far as I know, and has been up through 16.04 as well.

It seems that these are old unused packages that can be purged:

sudo apt purge `dpkg --list | grep ^rc | awk '{ print $2; }'`

(i found this info here: https://butwt.wordpress.com/2020/06/29/problems-upgrading-ubuntu-server-lts/ )