Intel cpus: get MAXPHYADDR at runtime for new CAR

Use CPUID to get MAXPHYADDR and set MTRR masks correctly.
Also only BSP CPU clears MTRRs and initializes its Local APIC.

Change-Id: I89ee765a17ec7c041284ed402f21d9a969d699bd
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/686
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-by: Idwer Vollering <vidwer@gmail.com>
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>