soc: rockchip: io-domain: Remove unneeded semicolon

Fix the following coccicheck warnings:

./drivers/soc/rockchip/io-domain.c:118:2-3: Unneeded semicolon.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Link: https://lore.kernel.org/r/1629361749-97977-1-git-send-email-jiapeng.chong@linux.alibaba.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>