Tweak byteserving code to work around a bug in Netscape Navigator that causes

it to only recognize multipart/x-byteranges, not multipart/byteranges (as per HTTP/1.1).

Reviewed by: Dean Gaudet, Jim Jagielski


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@77570 13f79535-47bb-0310-9956-ffa450edef68