This updates `fmt` to the latest version and moves to just being a copy
of their repo to make updating easier (no editing their cmake / figuring
out which files to minimally include).
The motivation for this is now that we switched to C++ 20, there were a
ton of deprecated function usages that is going away in future compiler
versions. This gets rid of all those warnings.
Normally, when they allocate a VagCmd, they do a bunch of stuff to clear
all the status bits and reset things
in particular the InitVAGCmd function does a lot
but for the stereo command, they do a lot less:
Which means that the new_stereo_command can just have random status bits
left over from whatever the last user had.
we seem to end up in a state where byte21 is set, and this causes
everything else to be wrong and off-by-one dma transfer. My guess is
that the original game avoided this bug due to lucky timing that I don't
understand.
I think the fix of just clearing byte21 is ok because there's no way
that the old value of the byte is useful after the command is
repurposed.
Tyler Wilding