mtd: OneNAND: return read error for 4KiB page read

When reading using the 4KiB page read function, I/O
errors could be ignored if more than 1 page was read
at a time.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>