[PATCH][MIPS] Add support for code_readable function attribute

[Robert Suchanek]

Hi Sandra,

> > +@item code_readable
> > +@cindex @code{code_readable} function attribute, MIPS
> > +For MIPS targets that support PC-relative addressing modes, this attribute
> > +can be used to control how an object is addressed.  The attribute takes
> > +a single optional argument:
> 
> The problem here is that we don't tell users that the argument has to be
> a string constant in quotes, and not just a token.
> 
> How about changing the above text to end with:
> 
> "...a single optional argument, which must be one of the following
> string constants:"

Indeed.  I'll include this change.

> 
> and then changing this to be @table @code and quoting the @item strings:

Likewise.

Regards,
Robert