cpu/intel/car/non-evict: Prepare for some POSTCAR_STAGE support

Prepare a common cache as ram for CPU's featuring a Non eviction mode
MSR.

Change-Id: I7fa3853498856050855b3b97546f4d31f66d12f7
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/26789
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
5 files changed