Handle device removal and removal+add cases to fix infinity rate. PR: 219829 Submitted by: ota@j.email.ne.jp Reported by: rezo@live.cn MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D25226
head/usr.bin/systat/ifcmds.c
head/usr.bin/systat/ifstat.c
head/usr.bin/systat/systat.1