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>

Also minor coding style cleanup.

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

The environment is the canonical storage location of the mac address, so
we're killing off the global data location and moving everything to
querying the env directly.

The cpus that get converted here:
	at91rm9200
	mpc512x
	mpc5xxx
	mpc8260
	mpc8xx
	ppc4xx

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
CC: Ben Warren <biggerbadderben@gmail.com>
CC: John Rigby <jrigby@freescale.com>
CC: Stefan Roese <sr@denx.de>

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

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>

Remove CONFIG_POST ifdefs from the post/ source files.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Wolfgang Denk <wd@denx.de>

Signed-off-by: Sergei Poselenov <sposelenov@emcraft.com>