staging: wfx: remove unused do_probe

The identifier do_probe is unused since "staging: wfx: remove workaround
to send probe requests"
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200115135338.14374-61-Jerome.Pouiller@silabs.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wfx/queue.c

@@ -365,7 +365,6 @@ static bool hif_handle_tx_data(struct wfx_vif *wvif, struct sk_buff *skb,
 	struct ieee80211_hdr *frame = (struct ieee80211_hdr *) (req->frame + req->data_flags.fc_offset);
 
 	enum {
-		do_probe,
 		do_drop,
 		do_wep,
 		do_tx,