docs/172980: Typo in deshallify.sh

[eadler at FreeBSD.org]

Synopsis: Typo in deshallify.sh

Responsible-Changed-From-To: freebsd-doc->eadler
Responsible-Changed-By: eadler
Responsible-Changed-When: Tue Oct 23 19:49:18 UTC 2012
Responsible-Changed-Why: 
I'll take it.

http://www.freebsd.org/cgi/query-pr.cgi?pr=172980