arm64: dts: imx8m: drop "fsl,aips-bus" and "fsl,imx8mq-aips-bus"

There is no binding doc for these compatible string
"fsl,imx8mq-aips-bus" and "fsl,aips-bus", "simple-bus" is enough
for aips usage, so drop the upper two.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>