patch applied (ghc): FIX #1533: foreign exporing the same identifier multiple times gave a link error

[Simon Marlow]

Tue Aug 28 02:15:50 PDT 2007  Simon Marlow <simonmar at microsoft.com>
  * FIX #1533: foreign exporing the same identifier multiple times gave a link error
  We were generating a new top-level binding derived from the name of
  the existing top-level name, and making the name external.  Multiple
  instances therefore clashed.  The fix is to make each name unique, by
  appending an actual Unique to the derived name.

    M ./compiler/typecheck/TcForeign.lhs -1 +13