Blackfin: convert specific pre/post config headers to common method

The Blackfin port was using asm/blackfin-config-{pre,post}.h to setup
common Blackfin board defines.  The common method now is to use config.h,
so convert blackfin-config-post.h to that.  Rename the still Blackfin
specific blackfin-config-pre.h to config-pre.h so the naming conventions
at least line up.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/include/configs/blackstamp.h b/include/configs/blackstamp.h
index f61e5b7..9cbc17a 100644
--- a/include/configs/blackstamp.h
+++ b/include/configs/blackstamp.h
@@ -8,7 +8,7 @@
 #ifndef __CONFIG_BLACKSTAMP_H__
 #define __CONFIG_BLACKSTAMP_H__
 
-#include <asm/blackfin-config-pre.h>
+#include <asm/config-pre.h>
 
 /*
  * Debugging: Set these options if you're having problems
@@ -270,6 +270,4 @@
 #undef CONFIG_CMD_JFFS2
 #undef CONFIG_CMD_FLASH
 
-#include <asm/blackfin-config-post.h>
-
 #endif