ul-2-testadapter: Also use mainline bsp and linux kernel 4.14
Use 'use-mainlinie-bsp' to include linux kernel 4.14-exceet. This kernel is required to support Winbond W25N02KV nand flash
Use 'use-mainlinie-bsp' to include linux kernel 4.14-exceet. This kernel is required to support Winbond W25N02KV nand flash