staging: rtl8192e: Remove variable ht_info->reg_short_gi_20mhz

ht_info->reg_short_gi_20mhz is set to 1 and unchanged. Therefore all
equations result accordingly and ht_info->reg_short_gi_20mhz can be
removed.
Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/a2778d12a2bb104a980a69f8eb05ba1cabf7b545.1702212003.git.philipp.g.hortmann@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192e/rtl819x_HT.h

@@ -97,7 +97,6 @@ struct rt_hi_throughput {
 	u8 cur_bw_40mhz;
 	u8 reg_short_gi_40mhz;
 	u8 cur_short_gi_40mhz;
-	u8 reg_short_gi_20mhz;
 	u8 cur_short_gi_20mhz;
 	u8 bCurSuppCCK;
 	enum ht_spec_ver ePeerHTSpecVer;

drivers/staging/rtl8192e/rtl819x_HTProc.c

@@ -71,7 +71,6 @@ void ht_update_default_setting(struct rtllib_device *ieee)
 {
 	struct rt_hi_throughput *ht_info = ieee->ht_info;
 
-	ht_info->reg_short_gi_20mhz = 1;
 	ht_info->reg_short_gi_40mhz = 1;
 
 	ht_info->amsdu_max_size = 7935UL;
@@ -471,9 +470,7 @@ void HTOnAssocRsp(struct rtllib_device *ieee)
 	ht_info->cur_tx_bw40mhz = ((pPeerHTInfo->RecommemdedTxWidth == 1) ?
 				 true : false);
 
-	ht_info->cur_short_gi_20mhz = ((ht_info->reg_short_gi_20mhz) ?
-				    ((pPeerHTCap->ShortGI20Mhz == 1) ?
-				    true : false) : false);
+	ht_info->cur_short_gi_20mhz = ((pPeerHTCap->ShortGI20Mhz == 1) ? true : false);
 	ht_info->cur_short_gi_40mhz = ((ht_info->reg_short_gi_40mhz) ?
 				     ((pPeerHTCap->ShortGI40Mhz == 1) ?
 				     true : false) : false);