POST cleanup.

- Revives POST for blackfin arch;
- Removes redundant code:
     arch/blackfin/lib/post.c
     arch/powerpc/cpu/ppc4xx/commproc.c
     arch/powerpc/cpu/mpc512x/common.c
- fixes up the post_word_{load|store} usage.

Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Acked-by: Detlev Zundel <dzu@denx.de>
Tested-by: Anatolij Gustschin <agust@denx.de>

List of the maintainers of the affected by patch boards:
Cc: Stephan Linz <linz@li-pro.net>
Cc: Denis Peter <d.peter@mpl.ch>
Cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>
Cc: Peter Tyser <ptyser@xes-inc.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Niklaus Giger <niklaus.giger@netstal.com>
Cc: Larry Johnson <lrj@acm.org>
Cc: Feng Kan <fkan@amcc.com>
diff --git a/include/configs/kilauea.h b/include/configs/kilauea.h
index 48dc946..8f813dd0 100644
--- a/include/configs/kilauea.h
+++ b/include/configs/kilauea.h
@@ -103,11 +103,10 @@
 
 #if defined(CONFIG_SYS_INIT_DCACHE_CS)
 # define CONFIG_SYS_INIT_SP_OFFSET	CONFIG_SYS_GBL_DATA_OFFSET
-# define CONFIG_SYS_POST_ALT_WORD_ADDR	(CONFIG_SYS_PERIPHERAL_BASE + GPT0_COMP6)
+# define CONFIG_SYS_POST_WORD_ADDR	(CONFIG_SYS_PERIPHERAL_BASE + GPT0_COMP6)
 #else
 # define CONFIG_SYS_INIT_EXTRA_SIZE	16
 # define CONFIG_SYS_INIT_SP_OFFSET	(CONFIG_SYS_GBL_DATA_OFFSET - CONFIG_SYS_INIT_EXTRA_SIZE)
-# define CONFIG_SYS_POST_WORD_ADDR	(CONFIG_SYS_GBL_DATA_OFFSET - 4)
 # define CONFIG_SYS_OCM_DATA_ADDR	CONFIG_SYS_INIT_RAM_ADDR
 #endif /* defined(CONFIG_SYS_INIT_DCACHE_CS) */