intel/sandybridge: Don't hardcode platform type

* Add a function to return CPU platform ID bits
* Add a function to return platform type
** Platform id is 4 on Lenovo T430 (mobile)
** Platform id is 1 on HP8200 (desktop)
* Use introduced method to handle platform specific code
* Use enum for platform type
* Report platform ID

Change-Id: Ifbfc64c8cec98782d6efc987a4d4d5aeab1402ba
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/22530
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/cpu/intel/model_206ax/Makefile.inc b/src/cpu/intel/model_206ax/Makefile.inc
index f6084ee..2c1d961 100644
--- a/src/cpu/intel/model_206ax/Makefile.inc
+++ b/src/cpu/intel/model_206ax/Makefile.inc
@@ -5,6 +5,10 @@
 
 ramstage-y += acpi.c
 
+ramstage-y += common.c
+romstage-y += common.c
+smm-$(CONFIG_HAVE_SMI_HANDLER) += common.c
+
 ramstage-y += tsc_freq.c
 romstage-y += tsc_freq.c
 smm-$(CONFIG_HAVE_SMI_HANDLER) += tsc_freq.c