audit: log failed attempts to change audit_pid configuration

Failed attempts to change the audit_pid configuration are not presently
logged.  One case is an attempt to starve an old auditd by starting up
a new auditd when the old one is still alive and active.  The other
case is an attempt to orphan a new auditd when an old auditd shuts
down.

Log both as AUDIT_CONFIG_CHANGE messages with failure result.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>