linuxkpi: Add more notifier defines
Needded by drm-kmod.
Reviewed by: bz, emaste, hselasky
Obtained from: drm-kmod
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: https://reviews.freebsd.org/D36018
(cherry picked from commit 7d2702a1983945210a1daa30b6e09ea7eb7b24d3)