Multi-arch and user-control of architecture flags

[Andrew Cagney]

> 
> Hmm, yep, that looks like what I want.
> 
> Note, however, there's something odd here...
> 
>   /* Add root prefix command for all "set mips"/"show mips" commands */
>   add_prefix_cmd ("mips", no_class, set_mips_command,
>                   "Various MIPS specific commands.",
>                   &setmipscmdlist, "set mips ", 0, &setlist);
> 
>   add_prefix_cmd ("mips", no_class, show_mips_command,
>                   "Various MIPS specific commands.",
>                   &showmipscmdlist, "show mips ", 0, &showlist);

> Then at the end of the file:
> 
>   /* Debug this files internals. */
>   add_show_from_set (add_set_cmd ("mips", class_maintenance, var_zinteger,
>                                   &mips_debug, "Set mips debugging.\n\
> When non-zero, mips specific debugging is enabled.", &setdebuglist),
>                      &showdebuglist);
> 
> One of these must shadow the other....

The latter is ``set debug mips''.  showdebuglist vs showmipscmdlist. 
Yes, bad variable names.

Andrew