patch 8.0.0447: getting font name does not work on X11

Problem:    Getting font name does not work on X11.
Solution:   Implement gui_mch_get_fontname() for X11.  Add more GUI tests.
            (Kazunobu Kuriyama)
diff --git a/src/version.c b/src/version.c
index cb416dc..caf1b64 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    447,
+/**/
     446,
 /**/
     446,