encoding the relative path.
This means that the kernel can be totally self contained now and is not dependent on the last buildworld to update /usr/share/mk. This might also make it easier to build 5.x kernels on 4.0 boxes etc, assuming gensetdefs and config(8) are updated.
PR: 16804 Submitted by: sascha@schumann.cx Approved by: jkh (release engineer)