staging: r8188eu: make _netdev_open() static

The function _netdev_open() is only used in os_intfs.c.
Make it static.

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20220911174933.3784-2-straube.linux@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/include/recv_osdep.h

@@ -16,7 +16,6 @@ void rtw_recv_returnpacket(struct  net_device *cnxt, struct sk_buff *retpkt);
 int rtw_init_recv_priv(struct recv_priv *precvpriv, struct adapter *padapter);
 void rtw_free_recv_priv(struct recv_priv *precvpriv);
 
-int _netdev_open(struct net_device *pnetdev);
 int netdev_open(struct net_device *pnetdev);
 int netdev_close(struct net_device *pnetdev);
 

drivers/staging/r8188eu/os_dep/os_intfs.c

@@ -617,7 +617,7 @@ void netdev_br_init(struct net_device *netdev)
 	rcu_read_unlock();
 }
 
-int _netdev_open(struct net_device *pnetdev)
+static int _netdev_open(struct net_device *pnetdev)
 {
 	uint status;
 	struct adapter *padapter = (struct adapter *)rtw_netdev_priv(pnetdev);