rtlwifi: rtl8192cu: Fix smatch warning in rtl8192cu/trx.c

Smatch lists the following:
  CHECK   drivers/net/wireless/rtlwifi/rtl8192cu/trx.c
drivers/net/wireless/rtlwifi/rtl8192cu/trx.c:367 _rtl_rx_process() warn: assigning (-98) to unsigned variable 'stats.noise'

This variable is unused, thus the initializer is removed, as well as a
comment referring to that variable.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rtlwifi/rtl8192cu/trx.c

@@ -349,7 +349,6 @@ bool rtl92cu_rx_query_desc(struct ieee80211_hw *hw,
 	}
 	/*rx_status->qual = stats->signal; */
 	rx_status->signal = stats->rssi + 10;
-	/*rx_status->noise = -stats->noise; */
 	return true;
 }
 
@@ -364,7 +363,6 @@ static void _rtl_rx_process(struct ieee80211_hw *hw, struct sk_buff *skb)
 	u8 *rxdesc;
 	struct rtl_stats stats = {
 		.signal = 0,
-		.noise = -98,
 		.rate = 0,
 	};
 	struct rx_fwinfo_92c *p_drvinfo;