All drm modules are added to the first and second stages, except
for nouveau and nvidia. Nouveau is added to stage2. nvidia needs
to be added to live and the base system separately. This is an
auxiliary target.

See also https://bugzilla.altlinux.org/31971

So much clearer and easier.
Thanks glebfm@ for the idea.

The actual certified branch is always the same, and at the moment
you need to use propagator in it.

Enable /proc for build vm/<target> and distro/<target> with use/stage2.
/proc needed for make-initrd >= 2.23.0.
See also https://bugzilla.altlinux.org/40900

Need to support initrd-bootchain in e2k feature.

Adds grub "Network installation" submenu and kernel modules to
initrd needed for network booting.

The drm feature solves the problem of creating a common entry
point for adding kernel drm modules for different package lists.
The need for allocation into a separate feature arose from one
parties to the need to make a switch between free and proprietary
NVIDIA driver, on the other, because of the need to add only drm
modules kernels for purposes such as use/stage2/kms and use/plymouth.

Also no more switch needed for RADEON, as only the free video driver
remains.

This list kernel modules for loading on single board computers.

This has manifested on e2k for me -- still using older
make-initrd lacking R: file -- so let's get this kludge
back for a while, or until any reasonable make-initrd
around has *everything* it needs to create images
listed in its runtime requirements.

Fixes: 2b3455c2

sin@ was kind enough to just stick mount.cifs into initrd
regardless of its presence in the chroot in question;
let's look first and only add what's found.

This started as a stopgap fix after make-initrd 2.2.0
which happened to collide with cifs-related m-p commits
in a somewhat unfortunate manner...

This has no users in master but out-of-tree branches might need
a trivial update.

The rationale is that it's actually for *any* stage2 and not related
to specifically "install" at all (otherwise it should have been moved
to install2 feature altogether).

Note that there's no reason to add nfs-utils similarly as make-initrd
requires kinit-utils which includes its own nfsmount.

This is sort of laying the ground for the future dismantling
of 10-stage2 (which was sub.in/stage1/modules just recently);
things look like tagged lists might become due some day, e.g.
"net+usb" or "scsi+raid" -- time will tell.

stage1's got prepare-modules target collecting
modules file snippets all over stage1/modules.d/
subdirectories within individual features.

stage2 now adds names of all the features going into
a particular image as snippet file suffix list so that
individual features don't have to register themselves
twice (as a feature and as a propagator modules.d
snippet carrier).

This is going to allow both "uncommon" modules getting
included with no problem (sin@ has wanted cifs ones
for quite some time, for example, and some want e.g.
infiniband modules) *and* to reduce the actual list
below the common mark as well (which is the case with
live-privacy image, for one).

And stage1 memory consumption does matter in some cases
as it's highly critical with no chance to use swap yet.

The newly-introduced STAGE1_KCONFIG variable serves
to keep those kernel configuration options that are
required to be present in the kernel to boot.

It would be better to put it into stage2 in the first place
but this somehow went over my head; rescue made a reminder.

The issue that appeared pretty hard to diagnose occured
to be the enhancement made in make-initrd-propagator=0.8.1-alt1.2
(that didn't hit Sisyphus until merged into 0.10-alt1) which
drops propagator dependency.

And that was optimized out in m-p, of course.

An initial draft of it was done half a year ago but several tricky
thingies had kept the code from showing up as it was rather brittle
and incomplete.

This implementation involves quite a few changes all over the place
but finally works good enough for live and installer images.

Please pay attention to the versions of these packages:
- installer-feature-setup-plymouth (0.3.2-alt1+)
- branding-altlinux-sisyphus (20110706-alt2+ if used)
- plymouth (0.8.3-alt20.git20110406+)

See also:
- http://www.altlinux.org/Branding
- http://www.altlinux.org/Plymouth

The features might get copy-pasted (or even copied-and-pruned)
when initialized; there's an unneccessary duplication of the
function name in the line adding it to FEATURES list, thus
prone to being forgotten and causing some havoc later on.

It was wrong in the first place but tackling this with some
double-colon rules ran into terminality issues, and further
tortures were considered unneccessary.

The current solution isn't perfect (no completely transparent
function name registration upon corresponding target being called)
but at least it is an improvement...

- introduced generic stage2 subprofile (non-standalone)
- ported installer and rescue over to stage2/{install2,rescue}
- initial stage2/live (needs more work for sure)
- use make-initrd-propagator
- updated and somewhat extended doc/

NB: mind #26133, #26134