patch 8.2.1237: changing 'completepopup' after opening popup has no effect

Problem:    Changing 'completepopup' after opening a popup has no effect. (Jay
            Sitter)
Solution:   Close the popup when the options are changed. (closes #6471)
diff --git a/src/popupwin.c b/src/popupwin.c
index 296441b..b0b4737 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -4031,6 +4031,18 @@
     if (wp != NULL)
 	popup_hide(wp);
 }
+
+/*
+ * Close any info popup.
+ */
+    void
+popup_close_info(void)
+{
+    win_T *wp = popup_find_info_window();
+
+    if (wp != NULL)
+	popup_close_with_retval(wp, -1);
+}
 #endif
 
 /*