Add support for nxp,imx8dxl-fspi, do the bindings document.
Signed-off-by: Kuldeep Singh <kuldeep.singh@nxp.com>
Link: https://lore.kernel.org/r/20210302124936.1972546-3-kuldeep.singh@nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>