workqueue: avoid using deprecated functions

The network merge brought in a few users of functions that got
deprecated by the workqueue cleanups: the 'system_nrt_wq' is now the
same as the regular system_wq, since all workqueues are now non-
reentrant.

Similarly, remove one use of flush_work_sync() - the regular
flush_work() has become synchronous, and the "_sync()" version is thus
deprecated as being superfluous.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/net/nfc/hci/hcp.c b/net/nfc/hci/hcp.c
index 208eedd..bc308a7 100644
--- a/net/nfc/hci/hcp.c
+++ b/net/nfc/hci/hcp.c
@@ -108,7 +108,7 @@
 	list_add_tail(&cmd->msg_l, &hdev->msg_tx_queue);
 	mutex_unlock(&hdev->msg_tx_mutex);
 
-	queue_work(system_nrt_wq, &hdev->msg_tx_work);
+	schedule_work(&hdev->msg_tx_work);
 
 	return 0;