arm64: dts: allwinner: a100: add watchdog node

Declare A100's watchdog in the device-tree.

Signed-off-by: Yangtao Li <frank@allwinnertech.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Cody Eksal <masterr3c0rd@epochal.quest>
Tested-by: Parthiban Nallathambi <parthiban@linumiz.com>
Link: https://patch.msgid.link/20241031070232.1793078-3-masterr3c0rd@epochal.quest


Signed-off-by: Chen-Yu Tsai <wens@csie.org>