ixgbe: if ixgbe_copy_dcb_cfg is going to fail learn about it early

Call ixgbe_copy_dcb_cfg() earlier in the ixgbe_dcbnl_set_all() so that
we can learn if this is going to fail as early as possible.  Previously,
ixgbe_down or ixgbe_close were being called before this check and the
IXGBE_RESETTING bit was being set and cleared.  Worse if this failed
the corresponding ixgbe_up/ndo_open would not called.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: PJ Waskiewicz <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>