mtd, ubi, ubifs: resync with Linux-3.14

resync ubi subsystem with linux:

commit 455c6fdbd219161bd09b1165f11699d6d73de11c
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun Mar 30 20:40:15 2014 -0700

    Linux 3.14

A nice side effect of this, is we introduce UBI Fastmap support
to U-Boot.

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Tom Rini <trini@ti.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Sergey Lapin <slapin@ossfans.org>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Joerg Krause <jkrause@posteo.de>
diff --git a/drivers/mtd/mtdcore.h b/drivers/mtd/mtdcore.h
new file mode 100644
index 0000000..7b03533
--- /dev/null
+++ b/drivers/mtd/mtdcore.h
@@ -0,0 +1,23 @@
+/*
+ * These are exported solely for the purpose of mtd_blkdevs.c and mtdchar.c.
+ * You should not use them for _anything_ else.
+ */
+
+extern struct mutex mtd_table_mutex;
+
+struct mtd_info *__mtd_next_device(int i);
+int add_mtd_device(struct mtd_info *mtd);
+int del_mtd_device(struct mtd_info *mtd);
+int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int);
+int del_mtd_partitions(struct mtd_info *);
+int parse_mtd_partitions(struct mtd_info *master, const char * const *types,
+			 struct mtd_partition **pparts,
+			 struct mtd_part_parser_data *data);
+
+int __init init_mtdchar(void);
+void __exit cleanup_mtdchar(void);
+
+#define mtd_for_each_device(mtd)			\
+	for ((mtd) = __mtd_next_device(0);		\
+	     (mtd) != NULL;				\
+	     (mtd) = __mtd_next_device(mtd->index + 1))