patch 8.2.5039: confusing error if first argument of popup_create() is wrong

Problem:    Confusing error if first argument of popup_create() is wrong.
Solution:   Give a more informative error.
diff --git a/src/popupwin.c b/src/popupwin.c
index 9687401..5074eaa 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -1047,7 +1047,7 @@
     {
 	if (li->li_tv.v_type != VAR_DICT)
 	{
-	    emsg(_(e_dictionary_required));
+	    semsg(_(e_argument_1_list_item_nr_dictionary_required), lnum + 1);
 	    return;
 	}
 	dict = li->li_tv.vval.v_dict;
@@ -1685,7 +1685,9 @@
 
 	if (l != NULL && l->lv_len > 0)
 	{
-	    if (l->lv_first->li_tv.v_type == VAR_STRING)
+	    if (l->lv_first == &range_list_item)
+		emsg(_(e_using_number_as_string));
+	    else if (l->lv_first->li_tv.v_type == VAR_STRING)
 		// list of strings
 		add_popup_strings(buf, l);
 	    else