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/korat.h b/include/configs/korat.h
index f95df68..23da72f 100644
--- a/include/configs/korat.h
+++ b/include/configs/korat.h
@@ -88,7 +88,7 @@
 #define CONFIG_SYS_INIT_RAM_END	(4 << 10)
 #define CONFIG_SYS_GBL_DATA_SIZE	256	/* num bytes initial data	*/
 #define CONFIG_SYS_GBL_DATA_OFFSET	(CONFIG_SYS_INIT_RAM_END - CONFIG_SYS_GBL_DATA_SIZE)
-#define CONFIG_SYS_INIT_SP_OFFSET	CONFIG_SYS_POST_WORD_ADDR
+#define CONFIG_SYS_INIT_SP_OFFSET	(CONFIG_SYS_GBL_DATA_OFFSET - 0x4)
 
 /*
  * Serial Port
@@ -306,7 +306,6 @@
 				 CONFIG_SYS_POST_SPR	| \
 				 CONFIG_SYS_POST_UART)
 
-#define CONFIG_SYS_POST_WORD_ADDR	(CONFIG_SYS_GBL_DATA_OFFSET - 0x4)
 #define CONFIG_LOGBUFFER
 #define CONFIG_SYS_POST_CACHE_ADDR	0xC8000000	/* free virtual address     */