Watchdog: Fix for the watchdog reset issue on OMAP3

Fix for the watchdog reset defect.The watchdog header file has been modified in the mainline merge due to which the watchdog was not functioning.
OMAP_WATCHDOG_BASE is being added twice so this patch is required for the watchdog to function.

Signed-off-by: Teerth Reddy <teerth@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>