hv_netvsc: use napi_schedule_irqoff

Since the netvsc_channel_cb is already called in interrupt
context from vmbus, there is no need to do irqsave/restore.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 4237ced..0265d70 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -1233,7 +1233,7 @@ void netvsc_channel_cb(void *context)
 		/* disable interupts from host */
 		hv_begin_read(rbi);
 
-		__napi_schedule(&nvchan->napi);
+		__napi_schedule_irqoff(&nvchan->napi);
 	}
 }