Merge r1642868 from trunk:

mpm_event: follow up to r1639614 (trunk) and r1642858 (2.4.x).

Notify suspend in any case when starting lingering close (blocking),
and outside the lingering queue's critical section.

Submitted by: ylavic
Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1645936 13f79535-47bb-0310-9956-ffa450edef68