[arch-haskell] cabal2arch 0.6.1 now generates bad dependencies

Hello again, cabal2arch 0.6.1 seems to only be generating dependencies consisting of ghc and haskell-cabal. This is problematic since ghc 6.12 already includes Distribution.Cabal and a few packages have dependencies besides these two :P This should be pretty easy to fix, but I'm willing to help if it's too boring to contemplate.