ppc/p4080: Add various p4080 related defines (and p4040)

There are various locations that we have chip specific info:

* Makefile for which ddr code to build
* Added p4080 & p4040 to cpu_type_list and SVR list
* Added number of LAWs for p4080
* Set CONFIG_MAX_CPUS to 8 for p4080

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>