ipmi: Periodically check to see if irqs and messages are set right

The BMC can be reset while we are running; that means the interrupt
and event message buffer settings may be wrong.  So periodically
check to see if these values are correct, and fix them if they
are wrong.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Tested-by: Tony Rex <tony.rex@ericsson.com>
Tested-by: Magnus Johansson E <magnus.e.johansson@ericsson.com>