Fix missing directory
Fix missing directory

See #289.

sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,izgzhen/hadrian,sdiehl/ghc,sdiehl/ghc,bgamari/shaking-up-ghc,snowleopard/shaking-up-ghc,snowleopard/hadrian,sdiehl/ghc,sdiehl/ghc