and fix new lints that come with it
It comes with a bunch of new lints (yay!) so I fixed them all so CI will keep working. Also apparently something about linking changed because I had to change the checks for deciding the linker flags for static x86_64 builds to keep working.
This is probably the most common target and usually doesn't involve cross compilation.
I *think* this will make it easier to pull in extra rustc targets.
