This was added in 0b9a72a62d38481ff08f742b2318d07f29ff5dff but became irrelevant in 70f9fc4e7526fc9cfc008a43cd33229f62be99b6 as the check is now self-explanatory due to a rejiggering of the bitfields.
Currently the logic for addressing the individual TexUnits is splattered all
across dolphin's codebase, this commit attempts to consolidate it all into a
single place and formalise it using our new TexUnitAddress struct.
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.
