ARM: rockchip: enable support for RK3228 SoCs

Add a rockchip,rk3228 compatible.
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/mach-rockchip/rockchip.c

@@ -82,6 +82,7 @@ static const char * const rockchip_board_dt_compat[] = {
 	"rockchip,rk3066a",
 	"rockchip,rk3066b",
 	"rockchip,rk3188",
+	"rockchip,rk3228",
 	"rockchip,rk3288",
 	NULL,
 };