arm64: dts: rockchip: RK356x: Add I2S2 device node

This patch adds I2S2 device tree node for RK3566/RK3568.

Signed-off-by: Shengyu Qu <wiagn233@outlook.com>
Link: https://lore.kernel.org/r/OS3P286MB259771C12F2B15A4DDF435FE98359@OS3P286MB2597.JPNP286.PROD.OUTLOOK.COM


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