econet: kill unnecessary spin_lock_init()

The spinlock aun_queue_lock is initialized statically. It is unnecessary
to initialize by spin_lock_init() at module load time.

This is detected by the semantic patch.

// <smpl>
@def@
declarer name DEFINE_SPINLOCK;
identifier spinlock;
@@

DEFINE_SPINLOCK(spinlock);

@@
identifier def.spinlock;
@@

- spin_lock_init(&spinlock);
// </smpl>

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>