Add SST39SF040 chip (like SST39SF020A but bigger - 4Mbit).
Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>