atl1c: fix issue of transmit queue 0 timed out

some people report atl1c could cause system hang with following
kernel trace info:
---------------------------------------
WARNING: at.../net/sched/sch_generic.c:258 dev_watchdog+0x1db/0x1d0()
...
NETDEV WATCHDOG: eth0 (atl1c): transmit queue 0 timed out
...
---------------------------------------
This is caused by netif_stop_queue calling when cable Link is down.
So remove netif_stop_queue, because link_watch will take it over.

Signed-off-by: xiong <xiong@qca.qualcomm.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Cloud Ren <cjren@qca.qualcomm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>