kconfig: prepend CT-NG's version tag to PKGVERSION

"crosstool-NG-${CT_VERSION}" is currently the default for TOOLCHAIN_PKGVERSION,
and this options is passed as is to --with-pkgversion.

This patch prepends "crosstool-NG ${CT_VERSION}" to TOOLCHAIN_PKGVERSION before
passing it to --with-pkgversion.

Signed-off-by: "Benoît THÉBAUDEAU" <benoit.thebaudeau@advansee.com>

functions: save & restore the static companion libraries install dir

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

functions: fix downloading files

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

cc/gcc: CC_STATIC_LIBSTDCXX 'depends on' CONFIGURE_has_static_libstdcpp

Hide the staticaly linked libstdc++ option if the static libstdc++ is not
present, detected at configure time.

Add a blind option that says whether static linking is possible at all.
It defaults to 'y', but depends on the needed CONFIGURE_* options. For
now, it only depends on static libtdc++, but new dependencies can be
easily added.

Hide the global static toolchain option behind this new option.

Original patch by Bryan Hundven <bryanhundven@gmail.com>

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

configure: check for libstdc++.{so,dylib,a}

It's probably a good thing to check for at least one instance of
libstdc++.{so,dylib,a} at configure time. At least one is needed
by the companion libraries and gcc.

Original patch by Bryan Hundven <bryanhundven@gmail.com>

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

configure: add prefix to err messages in has_or_{abort,warn}

Make it easier to spot messages spewed out by has_or_{abort,warn}.

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

configure: maintain single quotes in error messages

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

glibc: properly handle internal addons

Some addons are bundled with glibc/eglibc, so we should not try to
download and extract them.

This is done as thus:
- at download time:
- if the add-on download fails, keep going;
- at extract time:
- if the addon is present in the source tree, ignore it;
- if the addon is missing in the source tree:
- if the archive is present, extract it;
- if the archive is missing, bail out.

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

libc/eglibc: use generic SVN functions

eglibc is only available from SVN. The script currently calls svn
in its own tortuous and convoluted way.

Use the egeneric SVN extract functions, and sinplify the eglibc
download function.

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

scripts/functions: do not abort on failed svn

In case of eglibc, some add-ons that were previously external are
now internal (bundled with the main sources).

So we do not want to fail if an add-on can't be downloaded; we
want to post-pone the check until we can extract the main archive.

So:
- try to retrieve the add-on
- if it fails, print a warning instead of calling CT_Abort
- return 1

So, components that want to catch the error and want to handle it can,
while components that do not will gracefuly fail thanks to our catching
every errors.

Bonus: it works without changing any existing retrieval procedure! :-)

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