Stop checking to see if this is a pipelined request if we know

Stop checking to see if this is a pipelined request if we know
for a fact that it isn't.  Basically, if r->connection->keepalive == 0.
This keeps us from making an extra read call when serving a 1.0
request.
Submitted by:	  Ryan Bloom and Greg Stein

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@87738 13f79535-47bb-0310-9956-ffa450edef68