darcs patch: pass -B flag to help gcc find libraries ... (and 1 more)

Dear Windows GHC users, I can't easily test this but I am hoping you can :-) Duncan Wed Aug 27 13:44:36 BST 2008 dias@eecs.harvard.edu * pass -B flag to help gcc find libraries on Windows Thu Sep 11 01:11:36 BST 2008 Duncan Coutts <duncan@haskell.org> * Another attempt at gcc -B on Windows Only pass -B to gcc, but also pass through all extra gcc args to hsc2hs. This means it should work when we start using gcc directly elsewhere.