MLK-16841-1: dma: imx-sdma: add clock ration 1:1 check

On i.mx8 mscale B0 chip, AHB/SDMA clock ratio 2:1 can't be supportted,
since SDMA clock ration has to be increased to 250Mhz, AHB can't reach
to 500Mhz, so use 1:1 instead.

TODO: checkpatch warnings

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
Signed-off-by: Srikanth Krishnakar <Srikanth_Krishnakar@mentor.com>