Booting from USB NVMe enclosure

@Electr1 @hyphop I’m convinced my u-boot on SPI is whacked and that all I have is OOWOW in rescue mode (last in boot chain).

How do I actually restore my SPI to mint condition? I understand that there are scripts for this for older SBCs such as VIM3 and below, but how do I get this going on the Edge 2?