watchdog: fix hpwdt Kconfig regression in 3.0-rc

Remove Kconfig regression caused by commit
a4616153 "watchdog: hpwdt: build hpwdt as
module by default with NMI_DECODING enabled"

With the above change applied, hpwdt will be enabled unconditionally by just
entering the Watchdog subscreen in menuconfig. Since this driver is not
essential to boot any box it should remain disabled until it gets manually
enabled, just like all other drivers.
Signed-off-by: NOlaf Hering <olaf@aepfle.de>
Cc: Tony Camuso <tcamuso@redhat.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

drivers/watchdog/Kconfig

@@ -600,7 +600,6 @@ config IT87_WDT
 config HP_WATCHDOG
 	tristate "HP ProLiant iLO2+ Hardware Watchdog Timer"
 	depends on X86
-	default m
 	help
 	  A software monitoring watchdog and NMI sourcing driver. This driver
 	  will detect lockups and provide a stack trace. This is a driver that