soc: fsl: dpio: Prefer the CPU affine DPIO

Use the cpu affine DPIO unless there isn't one which can happen
if less DPIOs than cores are assign to the kernel.

Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Li Yang <leoyang.li@nxp.com>