Right now LOCK_DEBUG is enabled if KTR is on.
This is to support LOCK_LOG_* functionality effectively in debugging
environments but it is overkill because really LOCK_DEBUG should be on
only if (KTR_COMPILE & KTR_LOCK) is true.
Fix this by applying the correct logic.
In this process, move the KTR classes to its own header to reduce
namespace pollution.

Sponsored by:	EMC / Isilon storage division
Reviewed by:	jhb