Integrate uboot-imx-kuk/fix_board_detection

Commit: seco-ne/3rd-party/kuk/uboot-imx-kuk@255421d4

cmd:guf: Fix board detection of MC3

The board detection wasn't stable for the MC3 because it used a pin that could toggle. Reworked the detection for the MC3 to use a combination of fuses and processor type.