staging: wlan-ng: remove unused field from struct hfa384x_usbctlx

The variant field in struct hfa384x_usbctlx is not referenced anywhere
in the driver, so remove it.
Signed-off-by: Tim Collier <osdevtc@gmail.com>
Link: https://lore.kernel.org/r/20191025084126.9181-6-osdevtc@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wlan-ng/hfa384x.h

@@ -1181,8 +1181,6 @@ struct hfa384x_usbctlx {
 	ctlx_cmdcb_t cmdcb;	/* Async command callback */
 	ctlx_usercb_t usercb;	/* Async user callback, */
 	void *usercb_data;	/*  at CTLX completion  */
-
-	int variant;		/* Identifies cmd variant */
 };
 
 struct hfa384x_usbctlxq {