gcc-cross-sdk: Fix relocation of the toolchain and bump PR.

gcc-cross-sdk: Fix relocation of the toolchain and bump PR.
There's two parts to this. The first is to make relative, not absolute
symlinks for 'cpp', etc. The second is that we need to configure without
--with-gxx-include-dir and instead install the base C++ headers into the
expected location. The path passed to --with-gxx-include-dir will not be
relocated and is an absolute.

Acked-by: Florian Boor <florian.boor@kernelconcepts.de>
Acked-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Tom Rini <trini@embeddedalley.com>