i40e: Add a new variable to track number of pf instances

Track the number of physical functions (PFs) found, this is a global counter
on purpose so that each pf loaded has a unique ID.

Change-Id: I74d618520afbce4a774d0235449e3b5f97ff6d4a
Signed-off-by: Anjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 5aa2ea2..001d7cf 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -276,6 +276,8 @@
 	struct dentry *i40e_dbg_pf;
 #endif /* CONFIG_DEBUG_FS */
 
+	u16 instance; /* A unique number per i40e_pf instance in the system */
+
 	/* sr-iov config info */
 	struct i40e_vf *vf;
 	int num_alloc_vfs;	/* actual number of VFs allocated */