soc/intel/broadwell/pch: Use Lynx Point smbus.c

Continue unifying Lynx Point and Wildcat Point (PCH for Broadwell) code.
Define the WPT-LP SMBus PCI device ID, add it to smbus.c of Lynx Point,
and drop all now-unnecessary SMBus code from Broadwell.

Change-Id: I864d7c2dd47895a3c559e2f1219425cda9fd0c17
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51235
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

src/southbridge/intel/lynxpoint/smbus.c

@@ -40,6 +40,7 @@ static struct device_operations smbus_ops = {
 static const unsigned short pci_device_ids[] = {
 	PCI_DEVICE_ID_INTEL_LPT_H_SMBUS,
 	PCI_DEVICE_ID_INTEL_LPT_LP_SMBUS,
+	PCI_DEVICE_ID_INTEL_WPT_LP_SMBUS,
 	0
 };