NO_CLEAN: Utilize delete-old to remove old orphaned libraries/headers in WORLDTMP.

This prevents situations with -DNO_CLEAN from finding stale headers or
libraries in places that no longer exist or have moved. It avoids
the need to remove all of WORLDTMP by reusing what we already know
is obsolete.

MFC after: 1 month
Sponsored by: Dell EMC Isilon