There's no per-channel IRQ on mpc83xx, so only call free_irq if we have one.
Acked-by: NTimur Tabi <timur@freescale.com>
Acked-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NPeter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>