Signed-off-by: NWolfgang Denk <wd@denx.de>

Based on patch by Mike Frysinger, 20 Jun 2006

Modifications are based on the linux kernel approach and
support two use cases:

  1) Add O= to the make command line
  'make O=/tmp/build all'

  2) Set environement variable BUILD_DIR to point to the desired location
  'export BUILD_DIR=/tmp/build'
  'make'

The second approach can also be used with a MAKEALL script
'export BUILD_DIR=/tmp/build'
'./MAKEALL'

Command line 'O=' setting overrides BUILD_DIR environent variable.

When none of the above methods is used the local build is performed and
the object files are placed in the source directory.

Patch by Stefan Roese, 28 Feb 2006

Minimally modified patch by Bluetechnix, Vienna

  attempting to switch on USB on SX1 board.

* Patch by Josef Wagner, 18 Mar 2004:
  - Add support for MicroSys XM250 board (PXA255)
  - Add support for MicroSys PM828 board (MPC8280)
  - Add support for 32 MB Flash on PM825/826
  - new SDRAM refresh rate for PM825/PM826
  - added support for MicroSys PM520 (MPC5200)
  - replaced Query by Identify command in CPU86/flash.c
    to support 28F160F3B

* Fix wrap around problem with udelay() on ARM920T

* Add support for Macronix flash on TRAB board

  add support for Zephyr Engineering ZPC.1900 board

* Patch by Anders Larsen, 23 Sep 2003:
  add CMD_PORTIO to CFG_CMD_NONSTD (commands in question are only
  implemented for the x86 architecture)

  - remove trailing white space, trailing empty lines, C++ comments, etc.
  - split cmd_boot.c (separate cmd_bdinfo.c and cmd_load.c)

* Patches by Kenneth Johansson, 25 Jun 2003:
  - major rework of command structure
    (work done mostly by Michal Cendrowski and Joakim Kristiansen)