ktrace: Record cpuset violations with KTR_CAPFAIL

Report Capsicum violations in the cpuset namespace with CAPFAIL_CPUSET.

Reviewed by: markj
Approved by: markj (mentor)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D40677

(cherry picked from commit 96c8b3e509882e5a51a5ae58d366b812be4d2773)