device: Implement a bus agnostic dev_num_vf routine

Now that pci_bus_type has num_vf callback set, dev_num_vf can be
implemented in a bus type independent way and the check for whether a
PCI device is being handled in rtnetlink can be dropped.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/device.h b/include/linux/device.h
index 6d73b70..bd684fc 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -1144,6 +1144,13 @@
 extern void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
 extern void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode);
 
+static inline int dev_num_vf(struct device *dev)
+{
+	if (dev->bus && dev->bus->num_vf)
+		return dev->bus->num_vf(dev);
+	return 0;
+}
+
 /*
  * Root device objects for grouping under /sys/devices
  */