Fixes access for others to targets.log

We cannot get IMAGE_OUTPATH from the build.log, and there is currently
no other mechanism. Creating a CHECK directory was a bad idea. It should
have been created only for CHECK, but it was always created when DEBUG
was not enabled. So it's better to just issue a warning.

gnome-software already depends on it.

mcelog removed from Sisyphus in task 321924.
See: ALT bug 43075

See: https://bugzilla.altlinux.org/46271

See commit 1f066d54

too big for live.

Regression because of a commit 415d96da

Now lvm and cryptsetup are required not only in the
installed system, but also in altinst. This is because the remount
happens before the base system is installed.

wi-fi may also need to be configured in the installer.

This reverts commit 1076d79f.

The only workable xvt is xterm, since only works with it:

  xinit cmd

See commit: 2451a17c

Requested by Ivan A. Melnikov <iv@altlinux.org>

Use a prebuilt grub image for EFI, creating BOOT/EFI/grub.cfg

See ALT bug 31971