You need to create new configuration files similar as the following:
meta-qoriq/conf/machine/lx2160ardb-rev2.conf
meta-nxp-desktop/conf/machine/lx2160ardb-rev2distro.conf
meta-nxp-desktop/recipes-bsp/composite-firmware/qoriq-composite-firmware/lx2160ardb-rev2.manifest
meta-qoriq/recipes-bsp/secure-boot/secure-boot-qoriq/lx2160ardb-rev2.manifest
You need to modify recipes as the following to support your platform.
meta-nxp-desktop/recipes-bsp/u-boot/u-boot-script-distroboot_2020.04.bb
meta-qoriq/recipes-bsp/secure-boot/secure-boot-qoriq/create_secure_boot_image.sh
meta-qoriq/recipes-bsp/atf/qoriq-atf_2.6.bb
meta-qoriq/recipes-bsp/rcw/rcw_git.bbappend
meta-qoriq/recipes-fsl/images/fsl-image-kernelitb/kernel-arm64.its