rapidio/rionet: add shutdown event handling

rapidio/rionet: add shutdown event handling

Add shutdown notification handler which terminates active connections
with remote RapidIO nodes.  This prevents remote nodes from sending
packets to the powered off node and eliminates hardware error events on
remote nodes.

Signed-off-by: Alexandre Bounine <[email protected]>
Cc: Matt Porter <[email protected]>
Cc: Aurelien Jacquiot <[email protected]>
Cc: Andre van Herk <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>