ixgbe: move configuration of the MTQC register into it's own function

This patch moves the configuration of the MTQC register into it's own
function call similar to ixgbe_setup_mrqc.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>