If a removable device refuses to process PREVENT_ALLOW to lock the media in while the device is open, allow the open anyway. Fixes some USB devices which do odd things when presented by PREVENT_ALLOW.
If a removable device refuses to process PREVENT_ALLOW to lock the
media in while the device is open, allow the open anyway. Fixes some
USB devices which do odd things when presented by PREVENT_ALLOW.

Suggestion from mickey@.

ok millert@ marco@

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