Remove an extra argument to SYSCTL_FOREACH
This was missed in e0853c933661.
Approved by: re (cperciva, delphij)
Sponsored by: The FreeBSD Foundation
(cherry picked from commit fbc9f1b2d6cf90c02b918671fb7791cf36472cfd)
(cherry picked from commit f36ca798c42960383e0ff9612e56eb20c796cf04)