Apply fix from David Binderman via NetBSD. "Use all 3 of b, p, n
authorkrw <krw@openbsd.org>
Wed, 3 Aug 2016 23:22:48 +0000 (23:22 +0000)
committerkrw <krw@openbsd.org>
Wed, 3 Aug 2016 23:22:48 +0000 (23:22 +0000)
commit7f0e3e8df1a47581ec20d3554c6edcd010d4766d
tree182243f5679bd4a57a5887a668166cc4786e674c
parent5ae4c81e21152c3aec1e7a652d66222f43be3ed7
Apply fix from David Binderman via NetBSD. "Use all 3 of b, p, n
to determine if route changed".

Spotted by the Echelon team with AppChecker static analyzer.

NetBSD fix pointed out by millert@
usr.sbin/mtrace/mtrace.c