Old, obsolete and duplicated code was cleaned up and replace by the
new partitioning method. There are two possible approaches now:
* define a single, static partition
* use mtdparts command line option and dynamic partitioning
Default is static partitioning.
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)