installed obsolete files

[Thomas Klausner]

A from-scratch amd64 build just finished for me and reported:

Removed obsolete file 
${DEST}/usr/libdata/debug/usr/tests/kernel/t_timeleft.debug
Removed obsolete file ${DEST}/usr/include/x86/dbregs.h

I.e. those two files are installed by the build, but marked as
obsolete in the set lists.

What is the correct fix - stop installing them, or remove the
'obsolete' marker from the set lists?
 Thomas