mod_slotmem_shm: Fix balancers and balancer members slots reuse on

restart when new ones are added (Windows and OS/2 only).  PR 58024.

Since Windows and OS/2 don't have the unlink() but the "delete on last close"
semantic for opened files being removed, we can't reuse the same SHM files
names for processes of different generation.  Let's append the generation
number in the files names for those.

This commit also axes unused Unix specifics about mutexes/semaphores.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1702450 13f79535-47bb-0310-9956-ffa450edef68