PATCH: remove mach-o specific code in objdump.c

[Nick Clifton]

Hi Tristan,

> * dwarf segment name is not anymore __DWARFA (and furthermore the mach-o 
> backend now uses standard
>   elf names to make gdb happy)
> * there is no bias anymore.

What about old mach-o files ?  We need to be able to dump them properly 
as well.

Cheers
   Nick