igb: update name to reflect new hardware

This patch adds the 82576 device to the description for igb in Kconfig.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/Kconfig

@@ -1982,10 +1982,10 @@ config IP1000
 	  will be called ipg.  This is recommended.
 
 config IGB
-       tristate "Intel(R) 82575 PCI-Express Gigabit Ethernet support"
+       tristate "Intel(R) 82575/82576 PCI-Express Gigabit Ethernet support"
        depends on PCI
        ---help---
-         This driver supports Intel(R) 82575 gigabit ethernet family of
+         This driver supports Intel(R) 82575/82576 gigabit ethernet family of
          adapters.  For more information on how to identify your adapter, go
          to the Adapter & Driver ID Guide at: