a951e327e6
when we mount and get zero cost if no rules are used in a mountpoint. Add code to deref rules on unmount. Switch from SLIST to TAILQ. Drop SYSINIT, use SX_SYSINIT and static initializer of TAILQ instead. Drop goto, a break will do. Reduce double pointers to single pointers. Combine reaping and destroying rulesets. Avoid memory leaks in a some error cases.