[rndis] Add rndis_rx_err()

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/include/ipxe/rndis.h

 extern int rndis_tx_defer ( struct rndis_device *rndis,
 			    struct io_buffer *iobuf );
 extern void rndis_rx ( struct rndis_device *rndis, struct io_buffer *iobuf );
+extern void rndis_rx_err ( struct rndis_device *rndis, struct io_buffer *iobuf,
+			   int rc );
 
 extern struct rndis_device * alloc_rndis ( size_t priv_len );
 extern int register_rndis ( struct rndis_device *rndis );

src/net/rndis.c

 	netdev_rx_err ( netdev, iob_disown ( iobuf ), rc );
 }
 
+/**
+ * Discard packet from underlying transport layer
+ *
+ * @v rndis		RNDIS device
+ * @v iobuf		I/O buffer
+ * @v rc		Packet status code
+ */
+void rndis_rx_err ( struct rndis_device *rndis, struct io_buffer *iobuf,
+		    int rc ) {
+	struct net_device *netdev = rndis->netdev;
+
+	/* Record error */
+	netdev_rx_err ( netdev, iob_disown ( iobuf ), rc );
+}
+
 /**
  * Set receive filter
  *