* config/mips/irix6.mh: New file.
* config/mips/irix6.mt: New file.
* config/mips/xm-irix6.h: New file.
* config/mips/nm-irix6.h: New file.
* mips-tdep.c (mips_gdbarch_init) <MIPS_ABI_N32>: Set up the
disassembler info in tm_print_insn_info as appropriate for the N32
ABI. Force N32 ABI to be the default if the CPU is R8000 or
R10000.
* configure.tgt (mips*-sgi-irix6*): Map to irix6.
* configure.host (mips*-sgi-irix6*): Ditto.
