lx2160: Correct default environment variable

Create separate "boot_scripts" and "boot_script_hdr" environment
variable for LX2160A RDB and QDS board.

Signed-off-by: Meenakshi Aggarwal <meenakshi.aggarwal@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
3 files changed