[i.MX8MP] Add support for imx8mp lvds output
Changes based on patches from https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/Add-i-MX8MP-LVDS-driver-in-uboot/ta-p/1434826 and some other changes to make it work. Tested on Trizeps 8 Plus
Changes based on patches from https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/Add-i-MX8MP-LVDS-driver-in-uboot/ta-p/1434826 and some other changes to make it work. Tested on Trizeps 8 Plus