[RFA] get go32 target to compile again.

[Andrew Cagney]

>  The go32 target does not compile anymore.
> Eli told me that this is a main trunck only problem
> and that he was mainly interested in the 5.1 branch
> for the moment.
> 
>   Thus I tried to fix the compilation error myself.
> As I succeeded, I send here enclosed the patch.
> 
>    This probably make the regno_mapping.size field 
> not useful anymore, I suppose that we should trust regcache_collect
> function that it will use the correct size for each register.

Oops.  Eli's approval, but thanks!  I noticed this last night but hey, 
you've beaten me to it.

regcache_collect() always uses REGISTER_RAW_SIZE() so if it is of 
concern an assertion would be a good idea.

	Andrew