ubiformat: check file size ...

If size of a flash image file is 0 ubiformat silently formats the volume.
Check size and abort if size == 0. This may be the case if an empty or tftp
mounted file is used.

Signed-off-by: Jan Weitzel <j.weitzel@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ubiformat: get buffer from malloc ...

There was a erase block sized (here 131072) char buf array on the stack.
Changed this to get the space from malloc preventing stack overflows.
Also fix a wrong return without clean up.

Signed-off-by: Jan Weitzel <j.weitzel@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/mtd' ...

Conflicts:
	arch/arm/configs/eukrea_cpuimx27_defconfig
	drivers/mtd/core.c

ubiformat: open flash image readonly ...

ubiformat only needs readonly access to the image to flash, so
open it readonly. Opening r/w may fail for example on tftp servers.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libmtd: rename functions from mtd_* to libmtd_* ...

The kernel nowadays has mtd_read/write and other functions. In
barebox we also have these functions, but with a different prototype,
namely they correspond to the libmtd userspace functions. Rename
these functions to libmtd_* to avoid name clashes with future mtd
updates.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fixup! commands: add ubiformat ...

This adds the missing ubiformat.c file missing from:

commit 5a29d4a
Author: Wolfram Sang <w.sang@pengutronix.de>
Date:   Mon Dec 17 16:48:33 2012 +0100

    commands: add ubiformat

    Imported from mtd-utils and stripped down to needed functionality.
    Based on an older version (1.4.5.) since the newer do use MEMWRITE
    interfaces which we don't have in barebox (yet).

    Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
    Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>