UBI: make ubi-header.h local

The new trend in linux is not to store headers which define
on-media format in the include/ directory, but instead, store
them locally. This is because these headers "do not define any
kernel<->userspace interface".

Do so for UBI as well.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index a548c1d..28de80f 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -37,10 +37,9 @@
 #include <linux/string.h>
 #include <linux/vmalloc.h>
 #include <linux/mtd/mtd.h>
-
-#include <mtd/ubi-header.h>
 #include <linux/mtd/ubi.h>
 
+#include "ubi-media.h"
 #include "scan.h"
 #include "debug.h"