cc/gcc: fix linking with static PPL 0.11+

PPL 0.11+ installs three libs: lippl, libppl_c and libpwl.
libppl_c has a dependency on libpwl (at least for watchdog stuff).

While gcc correctly links with libppl and libppl_c, it does not
pull libpwl in. In case of shared libs, this is not a problem, as
libppl_c has a NEEDED dependency on libpwl. But for static libs,
that does not work. Although libppl_c.la exists and has a correct
dependency on lipwl, somehow gcc misses it. So we have to force
pulling libpwl when needed.

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

cc/gcc: hide Linaro options by default

It can be quite confusing for a new-comer to find strange
version numbers for gcc, so hide the Linaro versions by
default.

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

cc/gcc: add linaro 4.6 pre-release

Before gcc 4.6 was released, Linaro has a pre-release available.
Include that version in the config list.

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

cc/gcc: add 4.6.0

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

complibs/ppl: build watchdog library

gcc-4.6+ requires the Parma Watchdog Library (libpwl).
Build it and use it.

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

cc/gcc: prepare for upcoming 4.6

gcc 4.6 will no longer depend on libelf.

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

cc/gcc: cleanup the _or_later logic

So far, we've had a version always select appropriate _or_later option,
which in turn would select all previous _or_later options.

Because the dependencies on companion libs were cumulative, that was
working OK. But the upcoming 4.6 will no longer depend on libelf, so
we can't keep the cumulative scheme we've been using so far.

Have each release family select the corresponding dependencies, instead
of relying on selecting previous _or_later.

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

cc/gcc: update linaro versions

Linaro has released version linaro-4.5-2011.03-0.

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

cc/gcc: fix building core when building statically

There was a mishap when cut-n-pasting code from the final
step into the core step: a variable was not renamed.

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

kernel/linux: update version

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