Revert r255797.  The LK_UPGRADE | LK_NOWAIT drops the lock.

Approved by:	re (marius, implicit)
Build and install drill(1).

Approved by:	re (blanket)
Remove drill(1) if MK_LDNS_UTILS is false.
Remove host(1) if both MK_BIND and MK_LDNS_UTILS are false.

Approved by:	re (blanket)