ARM: samsung: Fix system restart on S3C6410

S3C6410 system restart is triggered by watchdog reset.

Cc: <stable@vger.kernel.org>
Fixes: 9f55342c ("ARM: dts: s3c64xx: Fix infinite interrupt in soft mode")
Signed-off-by: Lihua Yao <ylhuajnu@outlook.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>