mtd: mxc_nand: add correct dev_id parameter to free_irq() calls

Make sure to pass the same dev_id data to free_irq() that was
used when calling request_irq(), otherwise we get a warning about
freeing an already free IRQ.

Signed-off-by: Magnus Lilja <lilja.magnus@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>