Correct spelling of mod_spelling in update notice..

Submitted by:	"Singly Bertrand de (X1995)" <bs@frankiz.polytechnique.fr>


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@81891 13f79535-47bb-0310-9956-ffa450edef68