patch applied (ghc-6.6/ghc): add --force-files, like --force but doesn' t allow missing dependencies

[Ian Lynagh]

Mon Sep 18 16:28:34 PDT 2006  Simon Marlow <simonmar at microsoft.com>
  * add --force-files, like --force but doesn't allow missing dependencies

    M ./utils/ghc-pkg/Main.hs -24 +43