This driver adds /dev/watchdog support for the AMD sp5100 aka SB7x0 chipsets.

It follows the same conventions found in other /dev/watchdog drivers.
Signed-off-by: NPriyanka Gupta <priyankag@google.com>
Signed-off-by: NMike Waychison <mikew@google.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>