community/go: remove cgo files from misc/
Starting with >= 3.11.5 abuild complains about the size of the go-doc package. This is due to the size of cgo related files in misc/. These files will be moved elsewhere with Go 1.21 and do not seem to be needed really (since we haven't shipped them with the origin package). Hence we can just remove them for now to significantly reduce the go-doc package size.