[meta-xilinx] Reflash minized

[Philip Balister]

I've built an image for the minized from meta-xilinx-contrib successfully.

Before I start semi trial and erroring to get u-boot and the kernel into
qspi, has anyone written this process up?

On another note, the restore to factory instructions say you can use
Vivado 2017.1 or later. Well, 2018.3 fails with a u-boot error about
sfprobe 0 0 0 failing. I did install 2017.1 and confirm the procedure in
the documents does work for that version.

I realize the program_flash utility basically uses jtag to install
u-boot into memory and runs it, maybe we should just document this
process and avoid depending on magic tools that fail on different Vivado
versions.

Philip