convert ATM drivers to netdev_tx_t

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc net/atm/br2684.c
Simple merge

diff --cc net/atm/clip.c
Simple merge

diff --cc net/atm/lec.c
Simple merge

diff --cc net/atm/mpc.c
Simple merge