uboot-phytec

imx: imx8m: only support non-dm code in clock_imx8mm.c

The drivers/clk/imx/*.c are used for CLK dm case, the
clock_imx8mm.c is used for non CLK dm case, let's split
it. Sometimes it is hard to enable CLK dm in SPL stage,
considering code size, malloc size requirement, the splittion
will make it easy to use non CLK dm in SPL stage.

Signed-off-by: Peng Fan <peng.fan@nxp.com>