ra_serf: Now that we use the new serf API to create the request bucket, we shouldn't set the Host header anymore, as serf will do that for us.
ra_serf: Now that we use the new serf API to create the request bucket, we shouldn't
set the Host header anymore, as serf will do that for us.

* subversion/libsvn_ra_serf/util.c: Don't set Host header on requests when using
  serf version >= 0.4.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@896247 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion