Dear Maintainer,

The podman backend of autopkgtest can be used for tests that require the use of
an init system. This requires an image built with 'autopkgtest-build-podman
--init=<init-system>' (or other images built with an init system), and running
autopkgtest with args such as 'autopkgtest -- podman --init <image>'. These info
can be found and pieced together from the two manpages of autopkgtest-build-podman
and autopkgtest-virt-podman, but is nonetheless quite confusing and could take
a lot of iterations to reach the correct answer. This can be fixed by simply adding
an example to the autopkgtest-virt-podman manpage that contains the usage of the
podman backend with --init.

I have attached a patch to do the same. If doesn't matter if this very patch is not
accepted, I'd be happy as long as there is improvements to the manpage. If on the
other hand the patch needs some adjustments, or if you'd prefer a salsa MR, please
let me know so that I can do that.
Ananthu