mtd: spinand: Make sure continuous read is always disabled during probe

mtd: spinand: Make sure continuous read is always disabled during probe

Recent changes made sure whenever we were using continuous reads, we
would first start by disabling the feature to ensure a well proven and
stable probe sequence. For development purposes, it might also matter to
make sure we always disable continuous reads at first, in case the ECC
configuration would change. Doing this "automatically" will become even
more relevant when we add extra controller flags to prevent continuous
reads at all.

Ensure we disable continuous reads if the feature is available on the
chip, regardless of whether it will be used or not.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>