XXXX Intel X540 support

*** 708,722 ****
                          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.
                           */
!                         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] =
--- 708,722 ----
                          err = EINVAL;
                  else {
                          ixgbe->intr_throttling[0] = (uint32_t)result;
  
                          /*
!                          * 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)
                                  ixgbe->intr_throttling[0] =
                                      ixgbe->intr_throttling[0] & 0xFF8;
  
                          for (i = 0; i < MAX_INTR_VECTOR; i++)
                                  ixgbe->intr_throttling[i] =