gcc global register variables optimizer bug fix available

[Joe Buehler]

I have attached a patch for gcc 4.0.4 to gcc bug number 32820:

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32820

This patch allows building GHC 6.6.1 for HPUX/hppa with
optimization on.  I suspect that this is a cross-platform
gcc bug so ports to other platforms using gcc global register
variables are likely to need this patch.

I will make the optimized build for HPUX/hppa available
when I am done tweaking compiler options.  The optimized
ghc binary is half the size of the unoptimized one.

Joe Buehler