[POWERPC] Import spu disassembly code into xmon

This patch imports and munges the spu disassembly code from binutils.

All files originated from version 1.1 in binutils cvs.
 * spu.h, spu-insns.h and spu-opc.c are unchanged except for pathnames.
 * spu-dis.c has been edited heavily:
   * use printf instead of info->fprintf_func and similar.
   * pass the instruction in rather than reading it.
   * we have no equivalent to symbol_at_address_func, so we just assume
     there is never a symbol at the address given.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>