scripts: update tools

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

cc/gcc: enable plugins if needed

Enabling plugins in binutils is not enough, and gcc also
needs to be ./configured with --enable-plugins, although
this is not documented anywhere... :-/

Reported-by: karthik duraisami <kdconstant@hotmail.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

scripts: squash the multi-slash in the sysroot symlink

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

comptools: add make-3.81

Since the advent of make-3.82, some packages now break due to changes
in make-3.82, being stricter than 3.81 when interpreting the Makefiles.

This has bugged us a bit too much so far, and I believe fixing all
of them is a long road, while simply building make-3.81 is the easiest
route for now.

Of course, in the long term, packages will get fixed upstream, and we
should back-port the fixes to old versions, and get rid of building
make-3.81. In the meantime...

Reported several times on the mailing list.

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

config: add an option not to remove the destination directory

In certain circumstances, removing the destination/installation directory
is a bad idea. For example, when the build environment is already taking
care of sanitising the build tree, and pre-installs stuff in there, it is
a very bad idea to remove the destination directory.

This happens now in buildroot, as the crostool-NG backend now installs the
toolchain in the common host-tools directory, and pre-install there a few
host-utilities (eg. host-automake and host-gawk).

Provide a config knob to turn on/off the removal of the destination
directory, defaulting to 'y' (previous behavior), and forced to 'n' when
used as a backend.

Reported-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

samples: update the mingw sample

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

libc/mingw: do not remove support symlink

Under mingw, it seems that there is a mix between the traditional /usr
directory, and a similar-purposed /mingw directory (both in the sysroot).

Currently, we create /mingw as a symlink to /usr, and we removed it in
the libc-finish step.

Unfortunately, this prevents the pre-processor to find the headers.
Keeping the symlink makes it magically work...

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

config/toolchain: force use of sysroot if OBSOLETE is not set

Use of the sysroot is highly recommended, and the non-sysroot case is
both obsolete and not widely tested.

Before the non-sysroot case can go away, deprecate it.

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

scripts: fix double slash in paths

Computed paths may contain double slashes.
This is not an issue but it is just ugly to look at.

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

config: add an option to name the sysroot directory

Depending on local policies, some users have expressed a need to
have the sysroot be named differently than the hard-coded name.

Add an option for that.
Default to 'sysroot' to match the existing literature.

While at it, replace 'sys-root' with 'sysroot' everywhere we
reference the sysroot.

Reported-by: Alexey Kuznetsov <Alexey.KUZNETSOV@youtransactor.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>