powerpc/85xx: Add support for the "socrates" board (MPC8544)

[Wolfgang Grandegger]

Grant Likely wrote:
> I agree 100% with David's comments, and I have some additional ones below.
> 
> On Thu, Mar 19, 2009 at 9:26 AM, Wolfgang Grandegger <wg at grandegger.com> wrote:
>> +       soc8544 at e0000000 {
>> +               #address-cells = <1>;
>> +               #size-cells = <1>;
>> +               device_type = "soc";
> 
> Drop device_type here too.

Grrr, I just realized that removing the devices type "soc" has broken
fsl_get_sys_freq(). See:

http://lxr.linux.no/linux+v2.6.29/arch/powerpc/sysdev/fsl_soc.c#L80

We need a quick fix and we could take the occasion to establish a common
function for the MPC52xx as well, but it's not obvious to me how to find
the SOC node without the device type property.

Wolfgang.