net: cdc_ncm: drop "extern" from header declarations

Cc: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/usb/cdc_ncm.h

@@ -119,11 +119,11 @@ struct cdc_ncm_ctx {
 	u16 connected;
 };
 
-extern u8 cdc_ncm_select_altsetting(struct usbnet *dev, struct usb_interface *intf);
-extern int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting);
-extern void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf);
-extern struct sk_buff *cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign);
-extern int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in);
-extern int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset);
+u8 cdc_ncm_select_altsetting(struct usbnet *dev, struct usb_interface *intf);
+int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting);
+void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf);
+struct sk_buff *cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign);
+int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in);
+int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset);
 
 #endif /* __LINUX_USB_CDC_NCM_H */