Fix a truncation bug in how we print the port on the Via: header.

The routine that prints the Via: header now takes a length for
the port string.

Submitted by:	Zvi Har'El <rl@math.technion.ac.il>


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@91682 13f79535-47bb-0310-9956-ffa450edef68