open_posix_testsuite: Fix cross compilation of tools

by including config-openposix.mk which contains cross compilation setup.

This fixes #144.

Reported-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Petr Vorel <petr.vorel@gmail.com>
Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
1 file changed