XXXX Intel X540 support

@@ -708,15 +708,15 @@
                         err = EINVAL;
                 else {
                         ixgbe->intr_throttling[0] = (uint32_t)result;
 
                         /*
-                         * 82599 requires the interupt throttling rate is
-                         * a multiple of 8. This is enforced by the register
-                         * definiton.
+                         * 82599 and X540 require the interupt throttling
+                         * rate is a multiple of 8. This is enforced by the
+                         * register definiton.
                          */
-                        if (hw->mac.type == ixgbe_mac_82599EB)
+                        if (hw->mac.type >= ixgbe_mac_82599EB)
                                 ixgbe->intr_throttling[0] =
                                     ixgbe->intr_throttling[0] & 0xFF8;
 
                         for (i = 0; i < MAX_INTR_VECTOR; i++)
                                 ixgbe->intr_throttling[i] =