arm64: dts: rockchip: more user friendly name of sound nodes

This patch changes device name to more user friendly name of
Analog and SPDIF sound nodes for rk3399-rockpro64.

Signed-off-by: Katsuhiro Suzuki <katsuhiro@katsuster.net>
Link: https://lore.kernel.org/r/20210110151913.3615326-1-katsuhiro@katsuster.net


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