uboot-imx

watchdog: Convert Xilinx Axi watchdog driver to driver model

Xilinx Axi wdt driver conversion to driver model & Kconfig update
for the same.

Signed-off-by: Shreenidhi Shedi <yesshedi@gmail.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>