clk: imx8mp: Add ECSPI clocks

Add clock tables required for bing up ECSPI interfaces

Signed-off-by: Elmar Albert <ealbert@data-modul.com>
Cc: Fabio Estevam <festevam@denx.de>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: uboot-imx <uboot-imx@nxp.com>
Signed-off-by: Elmar Albert <ealbert@data-modul.com>
Reviewed-by: Fabio Estevam <festevam@denx.de>