gdb: remove command_class enum class_deprecated

The class_deprecated enumerator isn't assigned anywhere, so remove it.
Commands that are deprecated have cmd_list_element::cmd_deprecated set
instead.

Change-Id: Ib35e540915c52aa65f13bfe9b8e4e22e6007903c
diff --git a/gdb/cli/cli-setshow.c b/gdb/cli/cli-setshow.c
index 42c2b15..dcb50ca 100644
--- a/gdb/cli/cli-setshow.c
+++ b/gdb/cli/cli-setshow.c
@@ -37,11 +37,7 @@ notify_command_param_changed_p (bool param_changed, struct cmd_list_element *c)
   if (!param_changed)
     return false;
 
-  if (c->theclass == class_maintenance || c->theclass == class_deprecated
-      || c->theclass == class_obscure)
-    return false;
-
-  return true;
+  return c->theclass != class_maintenance && c->theclass != class_obscure;
 }
 
 
diff --git a/gdb/command.h b/gdb/command.h
index 9afe70c..d6e94b9 100644
--- a/gdb/command.h
+++ b/gdb/command.h
@@ -46,7 +46,6 @@ enum command_class
      Note that help accepts unambiguous abbreviated class names.  */
 
   /* Special classes to help_list */
-  class_deprecated = -3,
   all_classes = -2,  /* help without <classname> */
   all_commands = -1, /* all */