[PATCH]: Add support for MacOSX 64bits target

[Nick Clifton]

Hi Tristan,

> I tested it manually on a very binary (ie objdump -xxx file).
> I have to run the testsuite.  However because only binutils/ are built 
> (no gas, no ld), I am not sure how
> the testsuite behaves.

Fair enough.  Please just try testing a non-MachO toolchain (eg 
i686-pc-linux-gnu) to make sure that there are no regressions.  (ie for 
paranoia's sake).  Then check the patch in.

Cheers
   Nick