cc/gcc: allow building a canadian bare-metal compiler

Previous addition of the canadian cross compiler did not allow
to build a baremetal only variant, no reason why this is not
allowed

Signed-off-by: Bart vdr. Meulen <bartvdrmeulen@gmail.com>

cc/gcc: fix cc symlink when executables have an extension

When building a cross-compiler for a host which depends
on file extensions the symlink for cc was not installed correctly

Signed-off-by: Bart vdr. Meulen <bartvdrmeulen@gmail.com>
[Yann E. MORIN: style fixes, enhancements, code prettying]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

libc/newlib: the m68k processor does not like unaligned

Disable unaligned access at least for mcpu32, m68010 and m68020.
These processors certainly do not like unaligned accesses.

Signed-off-by: Remy Bohmer <linux@bohmer.net>
(transplanted from faade25219ed565993b7b26357991d3130697515)

complibs/mpfr: fix extract

With MPFR 2.4.2, autoreconf needs to be run as well.
(transplanted from b376baa43a50e178915f8d5dac40d9408bf2e962)

cc/gcc: add 4.5.0

cc/gcc: add support for 4.5.0 or later versions

starting with 4.5.0, gcc requires libelf.

complibs/libelf: remove old versions

Those old versions are not suitable for use by gcc.

complibs/libelf: enable the host build

Host libelf is required by gcc-4.5.0

complibs/libelf: build target libelf in its own directory

debug/gdb: remove insight

Insight seems to be very slow to follow up on mainstreram gdb.
Latest snapshots are more than 6 months old.

Moreover, I don't have time to maintain insight support in crosstool-NG;
and, because I don't use it, I am unable to find any breakage.