arm64: dts: ls208xa: disable SD UHS-I modes by default on RDB

Currently SD UHS-I modes were enabled by default on LS208xARDB boards,
but the new LS2088ARDB RevF board didn't support them any more since SDHC
circuit had been reworked. This patch is to disable SD UHS-I modes by default
in case of any issue on LS2088ARDB RevF

Signed-off-by: yinbo.zhu <yinbo.zhu@nxp.com>
Acked-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>