arm64: dts: imx8m: fix aips dts node

Per binding doc fsl,aips-bus.yaml, compatible and reg is
required. And for reg, the AIPS configuration space should be
used, not all the AIPS bus space.

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