BUF_LOCKINIT(9) on FreeBSD

The text e4fb6c0be11e, as FreeBSD 5.3-RELEASE, FreeBSD 5.2.1-RELEASE, FreeBSD 5.2-RELEASE, FreeBSD 5.1-RELEASE, FreeBSD 5.0-RELEASE shipped it.

unlocks a locked buffer

BUF_LOCKINIT(9) on FreeBSD now