of: remove of_default_bus_ids

This list used was by only two platforms with all other platforms defining an
own list of valid bus id's to pass to of_platform_bus_probe.  This patch:

i)   copies the default list to the two platforms that depended on it (powerpc)
ii)  remove the usage of of_default_bus_ids in of_platform_bus_probe
iii) removes the definition of the list from all architectures that defined it

Passing a NULL 'matches' parameter to of_platform_bus_probe is still valid; the
function returns no error in that case as the NULL value is equivalent to an
empty list.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
[grant.likely@secretlab.ca: added __initdata annotations, warn on and return error on missing match table, and fix whitespace errors]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>