mtd: rawnand: cadence: fix incorrect device in dma_unmap_single

dma_map_single is using physical/bus device (DMA) but dma_unmap_single
is using framework device(NAND controller), which is incorrect.
Fixed dma_unmap_single to use correct physical/bus device.

Fixes: ec4ba01e ("mtd: rawnand: Add new Cadence NAND driver to MTD subsystem")
Cc: stable@vger.kernel.org
Signed-off-by: Niravkumar L Rabara <niravkumar.l.rabara@intel.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>