After updating to 1.0.24, MinGW fails to build libusb as a result of
numerous errors. So we build libusb their way and let them update the
nontrivial stuff.
This only applies to MinGW: the old path is still in use for Linux
toolchains as well as MSVC.
This will dynamically link libusb, since I hit build errors with the old
way we used to resolve the conflict with SDL2.
Given we have two libraries that seem to use the same identifier, we can
alter one of them so that the variable is used in place, effectively
changing the used identifier, but without altering the source of
libusb.
We can place the external in an inner folder and manage the custom files
necessary to integrate it with CMake directly. This allows us to
directly change how we use it with our build system, as opposed to
needing to change a fork.
lat9nq