We want platform triple prefixes and suffixes on derivation names to
be used consistently. The ideom this commit strives for is
- suffix means build != host, i.e. cross *built* packages. This is
already done.
- prefix means build != target, i.e. cross tools. This matches the
tradition of such binaries themselves being prefixed to disambiguate.]
Binutils and cctools, as build tools, now use the latter
- No more *Cross duplication for binutils on darwin either.
`cctools_cross` is merged into plain `cctools`, so `buildPackages`
chains alone are used to disambiguate.
- Always use a mashup of cctools and actual GNU Binutils as `binutils`.
Previously, this was only done in the native case as nobody had
bothered to implement the masher in the cross case. Implemented it
basically consisted of extending the wrapper to deal with prefixed
binaries.
