cc/gcc: Add the ability to build gcc from svn

I took some of the svn functionality from eglibc.

Signed-off-by: Bryan Hundven <bryanhundven@gmail.com>
[yann.morin.1998@free.fr: fix the conditional test in build script]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

python

import sys

sys.path.insert(0, '@@PREFIX@@/share/gcc-@@VERSION@@/python')

from libstdcxx.v6.printers import register_libstdcxx_printers

register_libstdcxx_printers (None)

end