isp(4): Style changes

Please tools/build/checkstyle9.pl as mentioned by imp@

PR: 271062
Reviewed by: imp, mav
Sponsored by: Technical University of Munich
Pull Request: https://github.com/freebsd/freebsd-src/pull/726

(cherry picked from commit 348ec8dc036bf4ba1f607bb8acb25a0358436cc7)