patch applied (cabal): Hack to supress a warning when building Cabal

[Duncan Coutts]

Thu Aug 23 14:26:45 PDT 2007  Duncan Coutts <duncan at haskell.org>
  * Hack to supress a warning when building Cabal
  Normally we'd warn if using a new format cabal file and a cabal-version >= 1.2
  field is not specified in the cabal file. However we cannot do this for cabal
  itself or we'd not be able to bootstrap. So we just supress the warning for
  the package "Cabal".

    M ./Distribution/PackageDescription.hs -1 +2