main core: Emit errors during the initial apr_app_initialize()

or apr_pool_create() (when apr-based error reporting is not ready).

Backport: r568779


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@569543 13f79535-47bb-0310-9956-ffa450edef68