* Simplify how the subiquity client is run on the serial console in the live
server environment, breaking a unit cycle that sometimes prevents
subiquity from starting up at all. (LP: #1888497)
* Do not set the password for the installer user via cloud-init as subiquity
can now do this itself. (LP: #1933523)
- drop ds-identify policy, not needed with improved cloud config
- drop disabling network, doesn't work with ip=
- fixup setting up the INSTALLER_ROOT mountpoint
- enable cloud-init
- make cloud-init handle the default/baked in networking configuration
- install and enable openssh-server for the installation only
- provide cloud.cfg that generates random installer user password
- disable subiquity on sclp_line0 line based console
