[WATCHDOG] ib700wdt.c small clean-up's

* Fix identation
* Add watchdog "mandatory" WDIOC_GETBOOTSTATUS ioctl
* On unexpected close -> since this is considered as
  a write to the watchdog device, make sure we ping a
  last time.

Signed-off-by: Wim Van Sebroeck <wim@iguana.be>