Make Kconfig more similar to newconfig: enable "HAVE_HIGH_TABLES" per default.

Signed-off-by: Stefan Reinauer <stepan@coresystems.de>

Index: src/Kconfig
===================================================================
--- src/Kconfig    (revision 4981)
+++ src/Kconfig    (working copy)
@@ -259,7 +259,7 @@
 
 config HAVE_HIGH_TABLES
     bool
-    default n
+    default y
     help
       This variable specifies whether a given northbridge has high table
       support.