bin/173039: [mv][patch] don't prompt the user if stdin isn't a TTY

[eadler at FreeBSD.org]

Synopsis: [mv][patch] don't prompt the user if stdin isn't a TTY

Responsible-Changed-From-To: freebsd-bugs->eadler
Responsible-Changed-By: eadler
Responsible-Changed-When: Wed Oct 24 21:24:36 UTC 2012
Responsible-Changed-Why: 
I'll take it.

http://www.freebsd.org/cgi/query-pr.cgi?pr=173039