src/socket_wrapper.c: fix copy on write leak of ~38M for every fork.

commit 0f8e90dd (src/socket_wrapper.c: fix mutex fork handling) let us touch the whole sockets array on every fork, because each element in the array has it's own mutex.

max_sockets=65535 * sizeof(struct socket_info_container)=592 = 38796720

This was designed for the use of robust shared mutexes when moving the sockets array into a shared memory file.

Until we really move to shared memory, we can use a single global mutex in order to avoid the copy on write leaking.

Signed-off-by: Stefan Metzmacher metze@samba.org