Merge r559837, r559999 from trunk:

Fix integer comparisons in mod_filter
PR: 41835


Rationalisation suggested by rpluem

Submitted by: niq
Reviewed by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@562442 13f79535-47bb-0310-9956-ffa450edef68