staging: rtl8192u: Correction of spelling mistake in comment.

Simple spelling correction.
Signed-off-by: John Whitmore <johnfwhitmore@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192u/ieee80211/rtl819x_HTProc.c

@@ -869,7 +869,7 @@ static u8 HTFilterMCSRate(struct ieee80211_device *ieee, u8 *pSupportMCS,
 	/*
 	 * TODO: fill suggested rate adaptive rate index and give firmware info
 	 * using Tx command packet we also shall suggested the first start rate
-	 * set according to our singal strength
+	 * set according to our signal strength
 	 */
 	HT_PickMCSRate(ieee, pOperateMCS);