Remove ap_send_fb and ap_send_fb_length. These functions don't make much

sense anymore, because the BUFFs that Apache used to use it for have all
been replaced with buckets.  BUFFs can't be used with filters, and Apache
doesn't use these functions anywhere anymore, so they need to go away now.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@86439 13f79535-47bb-0310-9956-ffa450edef68