Revert "fix: don't modify ssh_config for ubuntu-cpc projects (LP:1968873)"
This change triggered a bug in cloud-init (see LP:1968873). cloud-init
does not recongnize sshd options set in /etc/ssh/sshd_config.d/ and
cloud-init modifies directly /etc/ssh/sshd_config which gets then
overwritten by settings from /etc/ssh/sshd_config.d/ .
This reverts commit b54d24ff3310f7ace00ab08e0dacfdc89e026f1c.
The image created uses a UEFI bootflow, so we install grub for this board
only. We also need flash-kernel to install the dtb where grub can find
it.
This image is specifically architectured so that it can be installed on
a "factory" board, meaning using the u-boot firmware which was
originally implemented for Fedora, so we need the p3 partition that
embeds a uEnv.txt file to tell u-boot what/where to load next stage.