When running ./download all, we have the following error:
    resources/scripts/download/coreboot: Line 52: $1 is not set.

The ./download all command was broken by the following commit:
2bb805e2e07a7d3e1268a09d720ecd13e26af418 (download: Add --help in the
individual download scripts).

Reported-by: madbehaviorus[m] on #libreboot on liberachat
Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>

Without that fix we have the following warning during the download:
    Cloning into 'u-boot/u-boot'...
    warning: redirecting to https://source.denx.de/u-boot/u-boot.git/

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>

This should enable various distributions and build system to reuse
the generated script to deblob u-boot releases themselves.

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>

This should enable various distributions and build system to reuse
that blob to deblob u-boot releases themselves.

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>

This doesn't change the existing usage of the scripts:
- For the Coreboot script, before this change, all arguments that were
  passed were considered as board to download the Coreboot source code
  for.

  Here we added the '--help' and '--list-boards' arguments, so it
  should not be an issue as it is extremely unlikely that a board
  would be called '--help' or '--list-boards'.

- All the other scripts don't use any arguments so passing --help
  should not conflict with the existing usage.

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>

Once the tarball are released, it will enable distributions to use
these tarballs to produce deblobbed u-boot packages.

Note that the produced tarball is not reproducible yet. Because of
that it has to be trusted.

During a release, it's a good idea to sign the uncompressed tarball as
the various compression formats and associated tools make different
tradeoffs.

For instance with xz, xz -9e tends to compress really well with the
the most used xz[1] implementation, and most GNU/Linux users probably
already have it installed, but and the drawbacks is that the format is
very fragile[2].

The lzip format is more suited for long term archiving but its most
packaged implementation[3] is less likely to be already installed by
users than more well known formats like xz, bzip2 or gzip.

Being able to add more compression formats after the release is also
useful, for instance to accommodate different build systems or use
cases (like being able to build u-boot with less dependencies in
distributions like Guix, or building u-boot directly on devices which
don't have enough RAM for xz for instance).

[1]https://tukaani.org/xz/
[2]https://www.nongnu.org/lzip/xz_inadequate.html
[3]https://www.nongnu.org/lzip/

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>

build_error is supposed to be a file since it's created with touch.

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>