msg: always generate random nonce; don't try to reuse PID

msg: always generate random nonce; don't try to reuse PID

Too much of pain with containerized world. The autodection,
based on `getpid() == 1`, turned out to be problematic.
This patch removes it and switches the behavior to always
use a random-generated nonce.

Fixes: https://tracker.ceph.com/issues/57977
Signed-off-by: Radoslaw Zarzynski <rzarzyns@redhat.com>