configure: more autostuff compatibility

Ignore --program-prefix=...

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
(transplanted from d28b764334b8f8f3acfecafea3b52a6cc2e8a272)

configure: more autostuff compatibility

Ignore --program-prefix=...

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

kerenl/linux: update to latest versions

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

scripts: try the mirror even if downloads are forbidden

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

scripts/functions: use array variables for URLs list

This is needed later, when we'll conditionnally use both the
upstream and the mirror URLs.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

scripts/functions: always prefer the mirror

Currently, the mirror can be used either:
- as a fallback in case upstream is unavailable (default behavior)
- as the preferred source for downloads

But the most common use-case seems to provide a truely-LAN mirror
to speed up downloads in big corpos', and/or provide a 'trusted'
source for the tarballs.

So, make the following changes;
- if a mirror is specified, always try that before trying upstream

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

scripts/functions: cvs retrieval first tries the mirror for tarballs

The cvs download helper looks for the local tarballs dir to see if it
can find a pre-downloaded tarball, and if it does not find it, does
the actual fetch to upstream via cvs.

In the process, it does not even try to get a tarball from the local
mirror, which can be useful if the mirror has been pre-populated
manually (or with a previously downloaded tree).

Fake a tarball get with the standard tarball-download helper, but
without specifying any upstream URL, which makes the helper directly
try the LAN mirror.

Of course, if no mirror is specified, no URL wil be available, and
the standard cvs retrieval will kick in.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

configure: do not require svn

svn is needed to download eglibc from the upstream repository.
In some situations, though, it can happen that:
- the developpers' machines do not have svn
- a LAN mirror has been set-up with pre-downloaded eglibc tarballs
In this case, it makes sense not to hard-depend on svn.

So, if svn is missing, just say so, and add a comment in the
menuconfig.

Reported-by: ANDY KENNEDY <ANDY.KENNEDY@adtran.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

scripts/functions: svn retrieval first tries the mirror for tarballs

The svn download helper looks for the local tarballs dir to see if it
can find a pre-downloaded tarball, and if it does not find it, does
the actual fetch to upstream via svn.

In the process, it does not even try to get a tarball from the local
mirror, which can be useful if the mirror has been pre-populated
manually (or with a previously downloaded tree).

Fake a tarball get with the standard tarball-download helper, but
without specifying any upstream URL, which makes the helper directly
try the LAN mirror.

Of course, if no mirror is specified, no URL wil be available, and
the standard svn retrieval will kick in.

Reported-by: ANDY KENNEDY <ANDY.KENNEDY@adtran.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

scripts/functions: if no upstream URL is given, silently ignore that

When retrieving tarballs from upstream, if no URL was given, do not
fail; simmply ignore that fact.

This will be used later when the SVN helper will call the standard
helper to try the LAN mirror before trying svn.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>