staging: rtl8723bs: core: remove set but not used 'algthm'

Fix the following gcc warning:

drivers/staging/rtl8723bs/core/rtw_mlme_ext.c:1087:33: warning: variable
‘algthm’ set but not used [-Wunused-but-set-variable]
  unsigned int seq, len, status, algthm, offset;
                                 ^~~~~~

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200427032342.27211-5-yanaijie@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723bs/core/rtw_mlme_ext.c

@@ -1084,7 +1084,7 @@ unsigned int OnAuth(struct adapter *padapter, union recv_frame *precv_frame)
 
 unsigned int OnAuthClient(struct adapter *padapter, union recv_frame *precv_frame)
 {
-	unsigned int	seq, len, status, algthm, offset;
+	unsigned int	seq, len, status, offset;
 	unsigned char *p;
 	unsigned int	go2asoc = 0;
 	struct mlme_ext_priv *pmlmeext = &padapter->mlmeextpriv;
@@ -1103,7 +1103,6 @@ unsigned int OnAuthClient(struct adapter *padapter, union recv_frame *precv_fram
 
 	offset = (GetPrivacy(pframe)) ? 4 : 0;
 
-	algthm	= le16_to_cpu(*(__le16 *)((SIZE_PTR)pframe + WLAN_HDR_A3_LEN + offset));
 	seq	= le16_to_cpu(*(__le16 *)((SIZE_PTR)pframe + WLAN_HDR_A3_LEN + offset + 2));
 	status	= le16_to_cpu(*(__le16 *)((SIZE_PTR)pframe + WLAN_HDR_A3_LEN + offset + 4));