o validate Tx queue only in case of adapters which supports
  multi Tx queue.

  This patch is to fix regression introduced in commit
  aa4a1f7d
  "qlcnic: Enable Tx queue changes using ethtool for 82xx Series adapter"
Signed-off-by: NHimanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>