kern/163370: [bpf] [request] enable zero-copy BPF by default

[linimon at FreeBSD.org]

Old Synopsis: zero-copy BPF is disabled by default
New Synopsis: [bpf] [request] enable zero-copy BPF by default

Responsible-Changed-From-To: freebsd-bugs->freebsd-net
Responsible-Changed-By: linimon
Responsible-Changed-When: Mon Jan 16 01:32:37 UTC 2012
Responsible-Changed-Why: 
reclassify.

http://www.freebsd.org/cgi/query-pr.cgi?pr=163370