igc: Add comment

Separate interrupt and flag definitions.
Made the code clear.
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/igc/igc.h

@@ -57,6 +57,8 @@ extern char igc_driver_version[];
 
 /* Interrupt defines */
 #define IGC_START_ITR			648 /* ~6000 ints/sec */
+
+/* Flags definitions */
 #define IGC_FLAG_HAS_MSI		BIT(0)
 #define IGC_FLAG_QUEUE_PAIRS		BIT(3)
 #define IGC_FLAG_DMAC			BIT(4)