igb: fix init on 82575 with MNG enabled

This patch resolves an issue seen on 82575 adapters with managability
pass-thru enabled, which could cause the system to panic.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/igb/e1000_defines.h b/drivers/net/igb/e1000_defines.h
index 1006d53..ed748dc 100644
--- a/drivers/net/igb/e1000_defines.h
+++ b/drivers/net/igb/e1000_defines.h
@@ -340,6 +340,7 @@
 #define E1000_RXCSUM_PCSD      0x00002000   /* packet checksum disabled */
 
 /* Header split receive */
+#define E1000_RFCTL_LEF        0x00040000
 
 /* Collision related configuration parameters */
 #define E1000_COLLISION_THRESHOLD       15