apache-httpd-2.4: revert "enable building the 'event'-based mpm worker"

Commit 0c3d910cd027a926ffc8538ea60cf2da099d7808 didn't have any effect.
The 'event' MPM module isn't built because our version of APR is too old.
apr: Update to 1.5.0
aprutil: update from 1.5.2 to 1.5.3
apr-util: Cleanup

Add the required packages to buildInputs. Create a wrapper around
apr-1-config so that internal sed commands succeed.