watchdog: orion: Introduce per-SoC stop() function

watchdog: orion: Introduce per-SoC stop() function

In order to support other SoCs, it's needed to have a different stop()
implementation for each SoC. This commit adds no functionality, and it
consists of preparation work.

Signed-off-by: Ezequiel Garcia <[email protected]>
Reviewed-by: Guenter Roeck <[email protected]>
Acked-by: Jason Cooper <[email protected]>
Tested-by: Jason Gunthorpe <[email protected]>
Tested-by: Sebastian Hesselbarth <[email protected]>
Signed-off-by: Wim Van Sebroeck <[email protected]>