* Get (mostly) rid of CFG_MONITOR_LEN definition; compute real length
  instead CFG_MONITOR_LEN is now only used to determine  _at_compile_
  _time_  (!) if the environment is embedded within the U-Boot image,
  or in a separate flash sector.

* Cleanup CFG_DER #defines in config files (wd maintained only)
diff --git a/board/sixnet/flash.c b/board/sixnet/flash.c
index c201875..3bf2ff8 100644
--- a/board/sixnet/flash.c
+++ b/board/sixnet/flash.c
@@ -100,7 +100,7 @@
 	/* monitor protection ON by default */
 	flash_protect(FLAG_PROTECT_SET,
 		      CFG_MONITOR_BASE,
-		      CFG_MONITOR_BASE+CFG_MONITOR_LEN-1,
+		      CFG_MONITOR_BASE+monitor_flash_len-1,
 		      &flash_info[0]);
 #endif