staging: rtl8712: r8712_free_drv_sw(): Change return type

Change return type of r8712_free_drv_sw from u8 to void and remove its
return statement as it always returns the same value (_SUCCESS) and even
this value is never stored, checked or otherwise used.

Signed-off-by: Nishka Dasgupta <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/rtl8712/os_intfs.c

···
 	return ret;
 }
 
-u8 r8712_free_drv_sw(struct _adapter *padapter)
+void r8712_free_drv_sw(struct _adapter *padapter)
 {
 	struct net_device *pnetdev = padapter->pnetdev;
 
···
 	mp871xdeinit(padapter);
 	if (pnetdev)
 		free_netdev(pnetdev);
-	return _SUCCESS;
 }
 
 static void enable_video_mode(struct _adapter *padapter, int cbw40_value)

drivers/staging/rtl8712/usb_osintf.h

···
 void r8712_stop_drv_threads(struct _adapter *padapter);
 void r8712_stop_drv_timers(struct _adapter *padapter);
 int r8712_init_drv_sw(struct _adapter *padapter);
-u8 r8712_free_drv_sw(struct _adapter *padapter);
+void r8712_free_drv_sw(struct _adapter *padapter);
 struct net_device *r8712_init_netdev(void);
 
 #endif