audit: tie SECCOMP records to syscall

Since seccomp events are triggered by user activity, tie the SECCOMP
record to the syscall record to collect all records from the same event.

See: https://github.com/linux-audit/audit-kernel/issues/87



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