Revert "soc: imx8m: change to use platform driver"

With the SoC matching changed to a platform driver the match data
is available only after other drivers, which may rely on it are
already probed. This breaks at least the CAAM driver on i.MX8M.
Revert the change until all those drivers have been audited and
changed to be able to eal with match data being available later
in the boot process.

Fixes: 7d981405 ("soc: imx8m: change to use platform driver")
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Acked-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>