Code review comment for ~alfonsosanchezbeato/ubuntu/+source/flash-kernel:kria-support

Rather than add a dtb-install flag, can you just omit the unused dtb-id on boards where we shouldn't copy it?

The boot scripts between ZCU and Kria look very similar, it's very tempting to make a generic script with a zcu and kria config, call that xlnx boot script, and select through a templated "default = @FIT_DEFAULT_CONFIG@". But it's also ok to keep things simple and have two simple data files :-)