patch 8.1.2114: when a popup is closed with CTRL-C the callback aborts

Problem:    When a popup is closed with CTRL-C the callback aborts.
Solution:   Reset got_int when invoking the callback. (closes #5008)
diff --git a/src/popupwin.c b/src/popupwin.c
index 0681207..6b0b383 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -2763,7 +2763,12 @@
     // Emergency exit: CTRL-C closes the popup.
     if (c == Ctrl_C)
     {
+	int save_got_int = got_int;
+
+	// Reset got_int to avoid the callback isn't called.
+	got_int = FALSE;
 	popup_close_with_retval(wp, -1);
+	got_int |= save_got_int;
 	return 1;
     }