patch applied (ghc): Make sure GCC uses the Sparc V9 instruction set

[Roman Leshchinskiy]

Fri Aug 25 03:16:46 PDT 2006  Roman Leshchinskiy <rl at cse.unsw.edu.au>
  * Make sure GCC uses the Sparc V9 instruction set
  
  We only support Sparc V9 and better as V8 lacks an atomic CAS instruction
  which we need for SMP. This means that we have to pass -mcpu=v9 to GCC when
  compiling and assembling. Hardcoding the flag is hackish but seems to be
  our best bet at the moment. It can still be overridden by the user as GCC
  picks the best -mcpu flag regardless of the ordering.

    M ./compiler/main/DriverPipeline.hs +19