libc/glibc: correctly handle dual-bitness archs

If the selected ARCH is dual-bitness (eg. supports 32- and 64-bit),
then we need to know the correct place where to fetch some headers.
Currently, this applies only to x86 variants: i386 and x86_64.

scripts/functions: fix extraction

arch/alpha: cleanup Alpha code

config/arch: always select the adequate bitness

Even if the selected ARCH does not support different bitness (or we do
not support building with another bitness), still select the appropriate
bitness.

config/arch: also export bitness as a string

documentation: Remove refs to seemingly native toolchains issue

Remove references to the seemingly native toolchains do not build
issue as it seems to be fixed.

Signed-off-by: Richard Strand <richard.strand@icomera.com>

1.5: update version string to 1.5.3+hg

Tagging release 1.5.3

i1.5: update version string to 1.5.3

libc/uClibc: add patch to fix IP frames on BE targets

Pack netinet structs to be possible to use for creating
IP frames on big-endian targets.

Signed-off-by: Joachim Nilsson <jocke@vmlinux.org>
[yann.morin.1998@anciens.enib.fr: removed getline patch, already in]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
(transplanted from 5c246abe7716271c0ce31d980d92eb9a304995c8)