ARM: dts: rockchip: Add OTP gpio pinctrl to rk3288 tsadc node

Add the "init" anf "sleep" pinctrl as the OTP gpio state.
We need the OTP pin is gpio state before resetting the TSADC controller,
since the tshut polarity will generate a high signal.

"init" pinctrl property is defined by Doug's Patch[0].

Patch[0]:
https://patchwork.kernel.org/patch/7454311/

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>