drivers/net: remove unnecessary flush_scheduled_work() calls

janz-ican3, sh_eth, skge and vxge don't use workqueue at all and there
is no reason to flush the system_wq.  Drop flush_scheduled_work()
calls and references to workqueue.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Ramkrishna Vepa <ramkrishna.vepa@exar.com>
Cc: Sivakumar Subramani <sivakumar.subramani@exar.com>
Cc: Sreenivasa Honnur <sreenivasa.honnur@exar.com>
Cc: Jon Mason <jon.mason@exar.com>
Cc: netdev@vger.kernel.org

drivers/net/can/janz-ican3.c

@@ -1114,11 +1114,6 @@ static bool ican3_txok(struct ican3_dev *mod)
 /*
  * Recieve one CAN frame from the hardware
  *
- * This works like the core of a NAPI function, but is intended to be called
- * from workqueue context instead. This driver already needs a workqueue to
- * process control messages, so we use the workqueue instead of using NAPI.
- * This was done to simplify locking.
- *
  * CONTEXT: must be called from user context
  */
 static int ican3_recv_skb(struct ican3_dev *mod)
@@ -1251,7 +1246,6 @@ static irqreturn_t ican3_irq(int irq, void *dev_id)
  * Reset an ICAN module to its power-on state
  *
  * CONTEXT: no network device registered
- * LOCKING: work function disabled
  */
 static int ican3_reset_module(struct ican3_dev *mod)
 {
@@ -1262,9 +1256,6 @@ static int ican3_reset_module(struct ican3_dev *mod)
 	/* disable interrupts so no more work is scheduled */
 	iowrite8(1 << mod->num, &mod->ctrl->int_disable);
 
-	/* flush any pending work */
-	flush_scheduled_work();
-
 	/* the first unallocated page in the DPM is #9 */
 	mod->free_page = DPM_FREE_START;