Bluetooth: Move tx queue to struct l2cap_chan

tx_q is the queue used by ERTM mode.

Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

diff --cc include/net/bluetooth/l2cap.h
Simple merge

diff --cc net/bluetooth/l2cap_core.c
Simple merge

diff --cc net/bluetooth/l2cap_sock.c
Simple merge