[coreboot] patch: grow grafix memory, and fix PLL on dbe62

[ron minnich]

This grows graphics mem to 16M per artec's recommendation.

The PLL autoconfig works now, so move to an auto value instead of
manual config.

This does not fix the problem with the memory errors. We've still got
something wrong in memory, and it is not clear what.

Signed-off-by: Ronald G. Minnich

I forgot it in the patch.

ron