[POWERPC] mpc52xx: Update mpc52xx_psc structure with B revision changes

On the mpc5200b the ccr register is 32 bits wide while on the
mpc5200 it's only 16 bits. It's up to the driver to use the
correct format depending on the chip it's running on.

The 5200b also offers some more registers & status in AC97
mode. Again, if not running on a 5200b the driver should not
use those.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>