[gtk/suggestion-entry2] Fix up the warning

[Matthias Clasen <matthiasc src gnome org>]

commit 20422f98ab2acd8db94bdce6a15ca37163ac0630
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Aug 25 13:54:32 2020 -0400

    Fix up the warning
    
    It is misleading to complain about the factory here.

 gtk/gtksuggestionentry.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtksuggestionentry.c b/gtk/gtksuggestionentry.c
index 7b01c9cf1d..6fb30e281f 100644
--- a/gtk/gtksuggestionentry.c
+++ b/gtk/gtksuggestionentry.c
@@ -1129,8 +1129,8 @@ map_func (gpointer item, gpointer user_data)
     }
   else
     {
-      g_critical ("Either GtkSuggestionEntry:factory or GtkSuggestionEntry:expression "
-                  "must be set");
+      g_critical ("Either GtkSuggestionEntry:expression must be set "
+                  "or GtkSuggestionEntry:model must be a GtkStringList");
       g_value_set_string (&value, "No value");
     }