staging:rtl8192u:ieee80211: Fix smatch warning of function definition with external linkage

This patch fixes the warnings:
drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c:381:13: warning: function 'ieee80211_qurey_ShortPreambleMode' with external linkage has definition
drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c:395:1: warning: function 'ieee80211_query_HTCapShortGI' with external linkage has definition
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c

@@ -378,7 +378,7 @@ static void ieee80211_tx_query_agg_cap(struct ieee80211_device *ieee,
 		return;
 }
 
-extern void ieee80211_qurey_ShortPreambleMode(struct ieee80211_device *ieee, cb_desc *tcb_desc)
+void ieee80211_qurey_ShortPreambleMode(struct ieee80211_device *ieee, cb_desc *tcb_desc)
 {
 	tcb_desc->bUseShortPreamble = false;
 	if (tcb_desc->data_rate == 2)
@@ -391,7 +391,7 @@ extern void ieee80211_qurey_ShortPreambleMode(struct ieee80211_device *ieee, cb_
 	}
 	return;
 }
-extern	void
+void
 ieee80211_query_HTCapShortGI(struct ieee80211_device *ieee, cb_desc *tcb_desc)
 {
 	PRT_HIGH_THROUGHPUT		pHTInfo = ieee->pHTInfo;