ppc4xx: Move ppc4xx headers to powerpc include directory

This patch moves some ppc4xx related headers from the common include
directory (include/) to the powerpc specific one
(arch/powerpc/include/asm/). This way to common include directory is not
so cluttered with files.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/board/snmc/qs850/flash.c b/board/snmc/qs850/flash.c
index a26a679..b592285 100644
--- a/board/snmc/qs850/flash.c
+++ b/board/snmc/qs850/flash.c
@@ -25,7 +25,7 @@
  */
 
 #include <common.h>
-#include <ppc4xx.h>
+#include <asm/ppc4xx.h>
 #include <asm/u-boot.h>
 #include <asm/processor.h>
 
diff --git a/board/snmc/qs860t/flash.c b/board/snmc/qs860t/flash.c
index 48c2258..e725115 100644
--- a/board/snmc/qs860t/flash.c
+++ b/board/snmc/qs860t/flash.c
@@ -25,7 +25,7 @@
  */
 
 #include <common.h>
-#include <ppc4xx.h>
+#include <asm/ppc4xx.h>
 #include <asm/u-boot.h>
 #include <asm/processor.h>