[gitg] Fix deprecation for const

[Alberto Fanjul <albfan src gnome org>]

commit fe4f4e266c4ed8d248052a924e482867dbc2ea9a
Author: Alberto Fanjul <albertofanjul gmail com>
Date:   Sun Dec 1 10:34:14 2019 +0100

    Fix deprecation for const

 contrib/xml/xml-reader.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/contrib/xml/xml-reader.c b/contrib/xml/xml-reader.c
index 3e783a7a..10ff278d 100644
--- a/contrib/xml/xml-reader.c
+++ b/contrib/xml/xml-reader.c
@@ -335,7 +335,7 @@ xml_reader_load_from_stream (XmlReader     *reader,
    return TRUE;
 }
 
-G_CONST_RETURN gchar *
+const gchar *
 xml_reader_get_value (XmlReader *reader)
 {
   g_return_val_if_fail (XML_IS_READER (reader), NULL);
@@ -345,7 +345,7 @@ xml_reader_get_value (XmlReader *reader)
   return XML_TO_CHAR (xmlTextReaderConstValue (reader->xml));
 }
 
-G_CONST_RETURN gchar *
+const gchar *
 xml_reader_get_name (XmlReader *reader)
 {
   g_return_val_if_fail (XML_IS_READER (reader), NULL);
@@ -527,7 +527,7 @@ xml_reader_is_namespace (XmlReader   *reader,
    return (g_strcmp0 (XML_TO_CHAR(xmlTextReaderConstNamespaceUri (reader->xml)), ns) == 0);
 }
 
-G_CONST_RETURN gchar *
+const gchar *
 xml_reader_get_local_name (XmlReader *reader)
 {
    g_return_val_if_fail(XML_IS_READER (reader), NULL);