Not all systemd-based images need these settings,
so don't change +systemd alias.

See-also: https://lists.altlinux.org/pipermail/devel-distro/2019-July/001710.html

The builder-useradd package installs components of ALT build
environment into the system, namely gear, hasher, and git-core
required for those to work.

See commit 207cec89c4515fefa2b711acd06c645ed3bd0ee8.

KFLAVOURS can describe more than one kernel, get iterator back.

Fixes: 27674e29

- ppc64le support (glebfm@)
- build-vm hacked to build tarballs too (iv@ et al)
- p8.mk: dropped; along with other cleanups/fixups (antohami)

It was misleading already, and riscv64 is going to join the gang
(but not there yet) following aarch64, mipsel, ppc64le and more
e2k* subarches...

I've just borrowed glebfm@'s one introduced by commit
ec23a8ec before; this
still might be improved it seems.
Suggested-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>

When grub-install(1) works on non-virtualized PowerPC system it may
execute scripts from powerpc-utils package.

ieee1275boot bootloader support was added in mkimage 0.2.27.

Plymouth is (much more) portable, but our branding packages contain
bootsplash designs only on x86 nowdays.

...to create users root:alt and alt:root as per BaseALT's rebranding.

This allows one not to hope that only the packages of the desired
loader will be installed.

Should be done this way in the first place it seems.

(gkebfm@ thinks it was a terrible idea in the first place
and mike@ agrees; this is a rework TODO item)