Cleanup of redundant/useless header file inclusion.
ISC style lint, primarily for function declarations and standalone
comments -- ie, those that appear on a line without any code, which
should be written as follows:
/*
* This is a comment.
*/
Decrement granted read lock when releasing a read lock if there are no
pending write locks. This still allows fair queuing between read and
write locks but does not block on aquiring a new read relock if we are
below quota of active locks and there are no pending writes.