dtc: Enable and fix -Wcast-qual warnings

[Jon Loeliger]

> Enabling -Wcast-qual warnings in dtc shows up a number of places where
> we are incorrectly discarding a const qualification.  There are also
> some places where we are intentionally discarding the 'const', and we
> need an ugly cast through uintptr_t to suppress the warning.  However,
> most of these are pretty well isolated with the *_w() functions.  So
> in the interests of maximum safety with const qualifications, this
> patch enables the warnings and fixes the existing complaints.
> 
> Signed-off-by: David Gibson <david at gibson.dropbear.id.au>

Guess which follow-on patch didn't apply for the same reason?
Needed to look like this hand-modified hunk...

> Index: dtc/Makefile
> ===================================================================
> --- dtc.orig/Makefile	2008-07-04 16:54:38.000000000 +1000
> +++ dtc/Makefile	2008-07-04 16:54:38.000000000 +1000
> @@ -16,7 +16,7 @@
>  CONFIG_LOCALVERSION =
>  
>  CPPFLAGS = -I libfdt
> -CFLAGS = -Wall -g -Os -Wpointer-arith
> +CFLAGS = -Wall -g -Os -Wpointer-arith -Wcast-qual
>  
>  BISON = bison
>  LEX = flex

Applied.

jdl