Mk/Scripts: Add qa check for man pages

portmgr@ has been actively working on moving man pages from
${PREFIX}/man to ${PREFIX}/share/man. Majority of the ports belonging to
non-committers or aliases has been migrated to ${PREFIX}/share/man.
There are still around 1000+ ports remaining mainly from the committers.
portmgr@ has planned to make the hard change after the split of 2024Q3
after which ports that installs man pages in ${PREFIX}/man will no
longer build or will be BROKEN.

Approved by: portmgr