Provide `gdb --tui' functionality for the hardlink `gdbtui'.

--- ./gdb/gdb.c	1 Jan 2008 22:53:09 -0000	1.6
+++ ./gdb/gdb.c	20 Jun 2008 08:02:57 -0000
@@ -30,5 +30,19 @@ main (int argc, char **argv)
   args.argv = argv;
   args.use_windows = 0;
   args.interpreter_p = INTERP_CONSOLE;
+
+  if (argv[0])
+    {
+      char *s;
+
+      s = strrchr (argv[0], '/');
+      if (s)
+	s++;
+      else
+	s = argv[0];
+      if (strcmp (s, "gdbtui") == 0)
+	args.interpreter_p = INTERP_TUI;
+    }
+
   return gdb_main (&args);
 }