mtd: rawnand: arasan: Workaround a misbehaving prog type with NV-DDR

As explained in the comment introduced above the fix, the Arasan
controller driver starts an operation when the prog register is being
written with a "type" specific to the action to perform.

The prog type used until now to perform a CHANGE READ COLUMN with an SDR
interface was the PAGE READ type (CMD + ADDR + CMD +
DATA). Unfortunately, for an unknown reason (let's call this a silicon
bug) any CHANGE READ COLUMN performed this way in NV-DDR mode will fail:
the data ready flag will never be triggered, nor will be the transfer
complete flag. Forcefully, this leads to a timeout situation which is
not easy to handle.

Fortunately, it was spotted that sending the same commands through a
different prog register "type", CHANGE READ COLUMN ENHANCED, would work
all the time (even though this particular command is not supported by
the core and is only available in a limited set of devices - we only
care about the controller configuration and not the actual command which
is sent to the device). So let's use this type instead when a CHANGE
READ COLUMN is requested.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210505213750.257417-22-miquel.raynal@bootlin.com

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