docs/178813: [handbook] wrong portmaster command in freebsd upgrade instructions

[linimon at FreeBSD.org]

Old Synopsis: wrong portmaster command in freebsd upgrade instructions
New Synopsis: [handbook] wrong portmaster command in freebsd upgrade instructions

Responsible-Changed-From-To: freebsd-bugs->freebsd-doc
Responsible-Changed-By: linimon
Responsible-Changed-When: Mon May 27 23:31:30 UTC 2013
Responsible-Changed-Why: 
reclassify.

http://www.freebsd.org/cgi/query-pr.cgi?pr=178813