mtd: rawnand: Prevent crossing LUN boundaries during sequential reads

The ONFI specification states that devices do not need to support
sequential reads across LUN boundaries. In order to prevent such event
from happening and possibly failing, let's introduce the concept of
"pause" in the sequential read to handle these cases. The first/last
pages remain the same but any time we cross a LUN boundary we will end
and restart (if relevant) the sequential read operation.

Cc: stable@vger.kernel.org
Fixes: 003fe4b9

 ("mtd: rawnand: Support for sequential cache reads")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Tested-by: Martin Hundebøll <martin@geanix.com>
Link: https://lore.kernel.org/linux-mtd/20231215123208.516590-2-miquel.raynal@bootlin.com