device: Make pci_dev_ops_pci structure global

This patch makes pci_dev_ops_pci structure global so that
caller can make use of this structure using extern.

Change-Id: I8de919aacccbc062475fb04f59ffb4957d3460b9
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/22814
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/device/pci_device.c

@@ -734,7 +734,7 @@ void pci_dev_init(struct device *dev)
 }
 
 /** Default device operation for PCI devices */
-static struct pci_operations pci_dev_ops_pci = {
+struct pci_operations pci_dev_ops_pci = {
 	.set_subsystem = pci_dev_set_subsystem,
 };