arm64: defconfig: Enable Qualcomm watchdog driver

Enable the driver for the watchdog found in the application processor
subsystem on most modern Qualcomm platforms.

Tested-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>