CPU table removal comment

[Chris Johns]

Till Straumann wrote:
> I noticed that with the CPU table gone
> exinit now always calls bsp_xxx_hook().

IMO this should be a core constructor and exinit should know nothing about any 
of this. See PR1253.

> 
> While the BSP certainly can override these hooks
> by defining it's own versions there is currently
> no way to call the generic version from libbsp/shared
> from the BSP's 'special' hook -- something that I'd consider
> desirable.
> 
> IMO, an additional level of indirection is required
> (was previously provided by the CPU table).
> E.g., the bsp_xxx_hook()s could be simple
> wrappers  calling bsp_xxx_hook_generic().
> If a BSP provides it's own bsp_xxx_hook it still
> could call bsp_xxx_hook_generic() from there...
>

The BSP could have its own group of constructors which can be ordered.

Regards
Chris