ports/152024: Mk/bsd.port.mk: skip non-existent users in GIDs

[sunpoet at FreeBSD.org]

Old Synopsis: skip non-existent users in GIDs
New Synopsis: Mk/bsd.port.mk: skip non-existent users in GIDs

Responsible-Changed-From-To: freebsd-ports-bugs->portmgr
Responsible-Changed-By: sunpoet
Responsible-Changed-When: Mon Nov 8 01:15:37 UTC 2010
Responsible-Changed-Why: 
Mk/bsd.port.mk is portmgr's territory.

http://www.freebsd.org/cgi/query-pr.cgi?pr=152024