this rwlock conversion breaks procfs (in linux compat), as found out by Antoine Jacoutot.  back out for oga to look at when he gets back in touch with earth.
this rwlock conversion breaks procfs (in linux compat), as found out
by Antoine Jacoutot.  back out for oga to look at when he gets back in
touch with earth.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars