staging: rtl8188eu: use safe iterator in rtw_free_xmitframe_queue

Use list_for_each_entry_safe, we may delete list items while iterating
over the list.

Fixes: 23017c88 ("staging: rtl8188eu: Use list iterators and helpers")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210517201826.25150-6-martin@kaiser.cxSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8188eu/core/rtw_xmit.c

@@ -1329,17 +1329,15 @@ s32 rtw_free_xmitframe(struct xmit_priv *pxmitpriv, struct xmit_frame *pxmitfram
 
 void rtw_free_xmitframe_queue(struct xmit_priv *pxmitpriv, struct __queue *pframequeue)
 {
-	struct list_head *plist, *phead;
-	struct	xmit_frame	*pxmitframe;
+	struct list_head *phead;
+	struct	xmit_frame	*pxmitframe, *temp;
 
 	spin_lock_bh(&pframequeue->lock);
 
 	phead = get_list_head(pframequeue);
-	list_for_each(plist, phead) {
-		pxmitframe = list_entry(plist, struct xmit_frame, list);
-
+	list_for_each_entry_safe(pxmitframe, temp, phead, list)
 		rtw_free_xmitframe(pxmitpriv, pxmitframe);
-	}
+
 	spin_unlock_bh(&pframequeue->lock);
 }