Remove some warnings from the code. The buckets take a different

type for the length than the brigade functions do.  This moves the
len_read variable into the correct scope for the two times that it
is used, and defines it correctly for each scope.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@91417 13f79535-47bb-0310-9956-ffa450edef68