This patch adds kernel module for gpioths driver to avoid change of kernel configuration (thanks to @joel for idea).
Also it fixes following issues:
- typo in comment: no more -> no less (thanks to @rpokala)
- stop callout in function gpioths_detach() (issue found during kldunload testing)
- add critical_enter/exits to avoid preemption (thanks to Maxim Logunov, <spitty.pnz at gmail.com>)
- man page
- find way how to set hints without kernel conf change