patch applied (packages/filepath): jiggle with cpp magic

[Malcolm Wallace]

Fri Mar 30 06:22:49 PDT 2007  Malcolm.Wallace at cs.york.ac.uk
  * jiggle with cpp magic
  The use of cpp macros _as well as_ conditionals to define which
  modules to import is horrible.  More to the point, it breaks hmake,
  which (for good reason) only supports conditionals not macros.  Since
  the conditional-only mechanism is equal in power, there's no reason to
  use the more general macro facility.

    M ./System/FilePath.hs -4 +4