SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Continues the migration to using fmt.
Notably, this allows safely converting a map within USBUtils over to
containing string view instances, rather than std::string instances, as
fmt safely handles the formatting of string views.
This cleans up some of the code between core and UI for disassembling and dumping code blocks.
Should help the QT UI in bringing up its debug UI since it won't have to deal with this garbage now.