cc/gcc: build core compilers for canadian

Currently, we rely on an existing external cross-compiler targetting
the target, to build the C library.

This can pause quite a few problems if that compiler is different from
the one we are building, because it could introduce some ABI issues.

This patch removes this dependency, by building the core compilers
as we do for standard cross, and also by building the binutils and
gcc, for running on the build machine.

This means we no longer need to offer the cross-sompiler selection in
the menuconfig.

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

 syntax: glob

 # Generated files

 configure

 autom4te.cache

 config.log

 config.status

 Makefile

 *ct-ng*

 docs/*ct-ng*.1

 docs/*ct-ng*.1.gz

 paths.mk

 paths.sh

 scripts/crosstool-NG.sh

 scripts/saveSample.sh

 scripts/showTuple.sh

 kconfig/conf

 kconfig/?conf

 kconfig/**.o

 kconfig/**.dep

 kconfig/lex.backup

 kconfig/lex.zconf.c

 kconfig/zconf.hash.c

 kconfig/zconf.tab.c

 config/configure.in

 config.gen/

 .config

 .config.2

 # Temporaries

 .*.swp

 build.log

 .config.old

 # This is the place where toolchains are built

 .build/

 # .. and the legacy location

 targets/