mtd: m25p80: Add support for Macronix MX25L25655E

Untested, but expected to be compatible with MX25L25635E which I did
test.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>