*) Replace apr_psprintf with apr_pstrcat where the format strings only

  *) Replace apr_psprintf with apr_pstrcat where the format strings only
     contain %s to improve efficiency. Leave out error messages as they
     are not on a crtical code path and error message become less readable
     when taking out the format specifiers.
     trunk patch: http://svn.apache.org/1862270
     2.4.x patch: svn merge -c 1862270 ^/httpd/httpd/trunk .
     +1: minfrin, rpluem, ylavic

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1879524 13f79535-47bb-0310-9956-ffa450edef68