[smsc75xx] Expose functionality shared with LAN78xx devices

The LAN78xx datapath is essentially identical to that of the SMSC75xx.
Expose the transmit, poll, and bulk IN endpoint operations to allow
for reuse by the LAN78xx driver.

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

src/drivers/net/smsc75xx.c

  * @v smscusb		SMSC USB device
  * @ret rc		Return status code
  */
-static int smsc75xx_dump_statistics ( struct smscusb_device *smscusb ) {
+int smsc75xx_dump_statistics ( struct smscusb_device *smscusb ) {
 	struct smsc75xx_statistics stats;
 	int rc;
 
 }
 
 /** Bulk IN endpoint operations */
-static struct usb_endpoint_driver_operations smsc75xx_in_operations = {
+struct usb_endpoint_driver_operations smsc75xx_in_operations = {
 	.complete = smsc75xx_in_complete,
 };
 
 	usbnet_close ( &smscusb->usbnet );
 
 	/* Dump statistics (for debugging) */
-	smsc75xx_dump_statistics ( smscusb );
+	if ( DBG_LOG )
+		smsc75xx_dump_statistics ( smscusb );
 
 	/* Reset device */
 	smsc75xx_reset ( smscusb );
  * @v iobuf		I/O buffer
  * @ret rc		Return status code
  */
-static int smsc75xx_transmit ( struct net_device *netdev,
-			       struct io_buffer *iobuf ) {
+int smsc75xx_transmit ( struct net_device *netdev, struct io_buffer *iobuf ) {
 	struct smscusb_device *smscusb = netdev->priv;
 	int rc;
 
  *
  * @v netdev		Network device
  */
-static void smsc75xx_poll ( struct net_device *netdev ) {
+void smsc75xx_poll ( struct net_device *netdev ) {
 	struct smscusb_device *smscusb = netdev->priv;
 	uint32_t int_sts;
 	int rc;

src/drivers/net/smsc75xx.h

 	( sizeof ( struct smsc75xx_rx_header ) +		\
 	  ETH_FRAME_LEN + 4 /* possible VLAN header */ )
 
+extern struct usb_endpoint_driver_operations smsc75xx_in_operations;
+
+extern int smsc75xx_dump_statistics ( struct smscusb_device *smscusb );
+extern int smsc75xx_transmit ( struct net_device *netdev,
+			       struct io_buffer *iobuf );
+extern void smsc75xx_poll ( struct net_device *netdev );
+
 #endif /* _SMSC75XX_H */