Before this commit, weak symbols were not overridden by non-weak symbols
found in archive libraries when linking with recent versions of
binutils.  As stated in the System V ABI, "the link editor does not
extract archive members to resolve undefined weak symbols".

This commit changes all Makefiles to use partial linking (ld -r) instead
of creating library archives, which forces all symbols to participate in
linking, allowing non-weak symbols to override weak symbols as intended.
This approach is also used by Linux, from which the gmake function
cmd_link_o_target (defined in config.mk and used in all Makefiles) is
inspired.

The name of each former library archive is preserved except for
extensions which change from ".a" to ".o".  This commit updates
references accordingly where needed, in particular in some linker
scripts.

This commit reveals board configurations that exclude some features but
include source files that depend these disabled features in the build,
resulting in undefined symbols.  Known such cases include:
- disabling CMD_NET but not CMD_NFS;
- enabling CONFIG_OF_LIBFDT but not CONFIG_QE.

Signed-off-by: Sebastien Carlier <sebastien.carlier@gmail.com>

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

Signed-off-by: Jon Loeliger <jdl@freescale.com>

This is a compatibility step that allows both the older form
and the new form to co-exist for a while until the older can
be removed entirely.

All transformations are of the form:
Before:
    #if (CONFIG_COMMANDS & CFG_CMD_AUTOSCRIPT)
After:
    #if (CONFIG_COMMANDS & CFG_CMD_AUTOSCRIPT) || defined(CONFIG_CMD_AUTOSCRIPT)

Signed-off-by: Jon Loeliger <jdl@freescale.com>

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.

  - 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)

  - fix bug in BOOTP code (must use NetCopyIP)
  - update of CSB226 port
  - clear BSS segment on XScale
  - added support for i2c_init_board() function
  - update to the Innokom plattform

* Extend support for redundand environments for configurations where
  environment size < sector size

  Add support for i386 architecture and AMD SC520 board

* Patch by Pierre Aubert, 12 Nov 2002:
  Add support for DOS filesystem and booting from DOS floppy disk