ports/146456: Update Port: x11/libxcb to v1.6

[wen at FreeBSD.org]

Synopsis: Update Port: x11/libxcb to v1.6

Responsible-Changed-From-To: freebsd-ports-bugs->wen
Responsible-Changed-By: wen
Responsible-Changed-When: Wed May 12 06:15:38 UTC 2010
Responsible-Changed-Why: 
I'll take it.

http://www.freebsd.org/cgi/query-pr.cgi?pr=146456