[commit] Tighten memory read/write methods

[Andrew Cagney]

Mark Kettenis wrote:
>    Date: Thu, 27 Jan 2005 15:11:19 -0500
>    From: Andrew Cagney <cagney@gnu.org>
> 
>    Hello,
> 
>    This cleans up the {target_,}{read,write}_memory methods making the 
>    buffer parameter a bfd_byte (instead of "is it signed?" char)

In constant propogating I'm making the following mind numbing 
transformations:

char -> const bfd_byte
unsigned char -> const bfd_byte
void -> const void

The first two are important.  Some compilers [rightly] complain about 
incompatibility between signed/unsigned char; and on ppc with it's 
unsigned char, results just get weird.

We can certainly debate the merits of ISO vs BFD and bfd_byte vs void, 
however lets keep that debate separate to my current task - getting 
constants sufficiently propogated for me to do my next value.h commit 
which in turn finishes DW_OP_piece.

Andrew