[U-Boot] RFQ: Makefile cleanup

[Reinhard Meyer <u-boot@emk-elektronik.de>]

Dear Graeme Russ,
> P.S. Here's a thought I ended up discarding:
> Each board could have a main config with all the common configuration
> values and a number of secondary includes (which include the primary) for
> each specific configuration. The entry in boards.cfg would select a
> specific config_xxx.h file
>
> eg
>
> boards.cfg:
> TQM8260     powerpc  mpc8260  tqm8260  tqc  -
> TQM8260_AB  powerpc  mpc8260  tqm8260  tqc  -
>
> /include/configs/TQM8260_AB.h:
>
> #include "configs/TQM8260.h"
>
> #define MPC8260
> #define 200MHz
> #define L2_CACHE
> #define BUSMODE_60x

That would make more sense to me. But it would even more crowd the include/configs
directory. A while ago I had proposed to change over to:
include/configs/<vendor>/<board>.h but that was rejected.

[Observation:]
But if we really head for linux style *config we would need a
<board>_defconfig individually for each variant...
But I don't think we are there anytime soon.
Many configs contain conditionals and *config does not handle
long (multiline) strings nicely...

Best Regards,
Reinhard