net: atlantic: changes for multi-TC support

This patch contains the following changes:
* access cfg via aq_nic_get_cfg() in aq_nic_start() and aq_nic_map_skb();
* call aq_nic_get_dev() just once in aq_nic_map_skb();
* move ring allocation/deallocation out of aq_vec_alloc()/aq_vec_free();
* add the missing aq_nic_deinit() in atl_resume_common();
* rename 'tcs' field to 'tcs_max' in aq_hw_caps_s to differentiate it from
  the 'tcs' field in aq_nic_cfg_s, which is used for the current number of
  TCs;
* update _TC_MAX defines to the actual number of supported TCs;
* move tx_tc_mode register defines slightly higher (just to keep the order
  of definitions);
* separate variables for TX/RX buff_size in hw_atl*_hw_qos_set();
* use AQ_HW_*_TC instead of hardcoded magic numbers;
* actually use the 'ret' value in aq_mdo_add_secy();

Signed-off-by: Dmitry Bezrukov <dbezrukov@marvell.com>
Co-developed-by: Mark Starovoytov <mstarovoitov@marvell.com>
Signed-off-by: Mark Starovoytov <mstarovoitov@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>