watchdog: designware: Convert to DM and DT probing

Convert the designware watchdog timer driver to DM and add DT probing
support. Perform minor coding style clean up, like drop superfluous
braces. These ought to be no functional change.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chin Liang See <chin.liang.see@intel.com>
Cc: Dalon Westergreen <dwesterg@gmail.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Philipp Tomisch <philipp.tomisch@theobroma-systems.com>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Cc: Tien Fong Chee <tien.fong.chee@intel.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # roc-rk3399-pc
diff --git a/configs/socfpga_stratix10_defconfig b/configs/socfpga_stratix10_defconfig
index a83d991..26db40f 100644
--- a/configs/socfpga_stratix10_defconfig
+++ b/configs/socfpga_stratix10_defconfig
@@ -58,5 +58,6 @@
 CONFIG_DM_USB=y
 CONFIG_USB_DWC2=y
 CONFIG_USB_STORAGE=y
-# CONFIG_SPL_USE_TINY_PRINTF is not set
 CONFIG_DESIGNWARE_WATCHDOG=y
+CONFIG_WDT=y
+# CONFIG_SPL_USE_TINY_PRINTF is not set