vmxnet3: fix non static symbol warning

Fixes the following sparse warning:

drivers/net/vmxnet3/vmxnet3_drv.c:1645:1: warning:
 symbol 'vmxnet3_rq_destroy_all_rxdataring' was not declared. Should it be static?
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NShrikrishna Khare <skhare@vmware.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/vmxnet3/vmxnet3_drv.c

@@ -1639,7 +1639,7 @@ static void vmxnet3_rq_destroy(struct vmxnet3_rx_queue *rq,
 	}
 }
 
-void
+static void
 vmxnet3_rq_destroy_all_rxdataring(struct vmxnet3_adapter *adapter)
 {
 	int i;