configs: ns3: enable sp805 watchdog driver

Enable sp805 watchdog driver for ns3.

Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/bcm_ns3_defconfig b/configs/bcm_ns3_defconfig
index 66fbdb2..ab26617 100644
--- a/configs/bcm_ns3_defconfig
+++ b/configs/bcm_ns3_defconfig
@@ -37,5 +37,7 @@
 CONFIG_PINCTRL_SINGLE=y
 CONFIG_DM_SERIAL=y
 CONFIG_SYS_NS16550=y
+CONFIG_WDT=y
+CONFIG_WDT_SP805=y
 CONFIG_FAT_WRITE=y
 CONFIG_SPL_OF_LIBFDT=y