devicetree: Fix improper use of chip_operations

Auto-discoverable PCI devices do not require field .enable_dev
of chip_operations to be set. They are matched with PCI drivers
by the use of PCI vendor and device ID fields.

The name given for the chip_operations struct must match the
pathname the way it is present in the devicetree.cb files. If
there was no match, util/sconfig would currently choose to
use the empty weak declaration it creates in static.c file.

Change-Id: I684a087a1f8ee4e1a5fd83450cd371fcfdbb6847
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35096
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>

src/southbridge/intel/i82870/pcibridge.c

@@ -47,3 +47,7 @@ static const struct pci_driver pcix_driver __pci_driver = {
 	.vendor = PCI_VENDOR_ID_INTEL,
 	.device = PCI_DEVICE_ID_INTEL_82870_1F0,
 };
+
+struct chip_operations southbridge_intel_i82870_ops = {
+	CHIP_NAME("Intel 82870")
+};