Link against APR generation 1 still with httpd-2.4

Httpd-2.4 is still intended to be compiled with APR-1.x, so this reverts rev. 1222775 (on the trunk) and hence also revs. 1448043 & 1503135 (on this branch) which both worked around breakages caused by that premature switch to APR generation 2.

git-svn-id: https://svn.apache.org/repos/asf/perl/modperl/branches/httpd24@1508326 13f79535-47bb-0310-9956-ffa450edef68