copy_buildsystem.py: Pass the nativelsb argument to gen-lockedsig-cache
If the nativelsb argument is not used, then create_locked_sstate_cache()
can get collisions when moving the files from the input_sstate_cache
to the output_sstate_cache.
The specific case where this was encountered was when a "universal"
nativelsb directory already existed in the input_sstate_cache.
Signed-off-by: Randy Witt <randy.e.witt@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
