[PATCH] system: change our notification fd handling

[PATCH] system: change our notification fd handling

This commit changes how we handle the notification fd by only
requesting it via _NEW_LISTENER if the filter has a _NOTIFY action
in it.  We also augment the seccomp_reset(NULL, ...) behavior so
that it closes the notification fd before resetting the global
state; applications that need to keep their notification fd open
across a call to seccomp_reset(NULL, ...) can simply dup() it.
Although one would have to wonder why the application would be
calling seccomp_reset(NULL, ...) in that case.

Acked-by: Tom Hromatka <tom.hromatka@oracle.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
(imported from commit 02812f99e8d1df2e671dac675b4af663d0266303)

Gbp-Pq: Name system_change_our_notification_fd_handling.patch