Return 413 if chunk-ext-header is too long rather than reading from a truncated

line.

(Previously, we'd count the unread part of the line towards the chunk.)

PR: 15857


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@98727 13f79535-47bb-0310-9956-ffa450edef68