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/northbridge/intel/sandybridge/early_init.c b/src/northbridge/intel/sandybridge/early_init.c
index 2f1b790..7b4b3be 100644
--- a/src/northbridge/intel/sandybridge/early_init.c
+++ b/src/northbridge/intel/sandybridge/early_init.c
@@ -186,7 +186,7 @@
 	}
 }
 
-void sandybridge_early_initialization(int chipset_type)
+void sandybridge_early_initialization(void)
 {
 	u32 capid0_a;
 	u32 deven;
@@ -195,10 +195,12 @@
 	/* Device ID Override Enable should be done very early */
 	capid0_a = pci_read_config32(PCI_DEV(0, 0, 0), 0xe4);
 	if (capid0_a & (1 << 10)) {
+		const size_t is_mobile = get_platform_type() == PLATFORM_MOBILE;
+
 		reg8 = pci_read_config8(PCI_DEV(0, 0, 0), 0xf3);
 		reg8 &= ~7; /* Clear 2:0 */
 
-		if (chipset_type == SANDYBRIDGE_MOBILE)
+		if (is_mobile)
 			reg8 |= 1; /* Set bit 0 */
 
 		pci_write_config8(PCI_DEV(0, 0, 0), 0xf3, reg8);