localedef: new package

This host only package allows to build the localedef program, which is
needed to generate locale data for (e)glibc-based systems. The source
code has been extracted from the eglibc sources and put inside a small
and nice tarball by the PTXdist developers, which makes it easy and
convenient to build for the host.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>