The systemd 254.2-1 package ships with IA32 systemd-boot, so it is
possible to use for booting on IA32 UEFI.
Perhaps they will be useful in the future.
At least for now, the baseline and releng profiles are not changed to
use them. When the issues and headaches caused with GRUB reach a
critical point, then we will switch.
docs/README.profile.rst:
Add documentation for the optional `buildmodes` array in profiledef.sh, the understood build modes `bootstrap` and
`iso` and the implicit default build mode 'iso'.
Add basic documentation for the bootstrap_packages.arch file.
Add missing backticks.
Fix indent.
