uclibc: add ability to use uClibc-ng 1.0.0

This commit adds support for a new uClibc version: uClibc-ng
1.0.0. Since its build system is for now exactly the same as the one
of uClibc, we don't create a new package, but instead simply add it as
a new uClibc version.

The only special trick needed is the creation of a symlink to the
program interpreter, due to a mismatch between the program interpreter
file name generated by uClibc-ng and the one used by gcc.

This patch is heavily based on previous work from Waldemar Brodkorb.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Waldemar Brodkorb <wbx@uclibc-ng.org>