audit: reset audit backlog wait time after error recovery

When the audit queue overflows and times out (audit_backlog_wait_time), the
audit queue overflow timeout is set to zero.  Once the audit queue overflow
timeout condition recovers, the timeout should be reset to the original value.

See also:
	https://lkml.org/lkml/2013/9/2/473



Cc: stable@vger.kernel.org # v3.8-rc4+
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Dan Duval <dan.duval@oracle.com>
Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>