arm64: dts: rockchip: add Hynitron cst340 for Anbernic 353 series

Add support for the Hynitron cst340 touchscreen driver to the Anbernic
RG353P and RG353V devices. Note the RG353VS device does not have a
touchscreen.

https://lore.kernel.org/linux-input/Y1y9e9sgE%2FDck9fB@google.com/



Changes since V1:
 - Removed 'status = "okay";', as it was never disabled.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Link: https://lore.kernel.org/r/20221128231528.23360-1-macroalpha82@gmail.com


Signed-off-by: Heiko Stuebner <heiko@sntech.de>