igb: access to NIC time

Adds the register definitions and code to read the time
register.

Signed-off-by: John Ronciak <john.ronciak@intel.com>
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/igb/igb.h b/drivers/net/igb/igb.h
index e507449..797a9fe 100644
--- a/drivers/net/igb/igb.h
+++ b/drivers/net/igb/igb.h
@@ -34,6 +34,8 @@
 #include "e1000_mac.h"
 #include "e1000_82575.h"
 
+#include <linux/clocksource.h>
+
 struct igb_adapter;
 
 /* Interrupt defines */
@@ -251,6 +253,8 @@
 	struct napi_struct napi;
 	struct pci_dev *pdev;
 	struct net_device_stats net_stats;
+	struct cyclecounter cycles;
+	struct timecounter clock;
 
 	/* structs defined in e1000_hw.h */
 	struct e1000_hw hw;