This patch adds the appropriate conversions to correct the endianness
issues in the MTD driver whenever it accesses the device tree (which is
always big endian).

Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>