The IRQ number is needed after probe to be able to add synchronisation
points in other places in the driver when freeing resources and to
implement a device_synchronize() callback. Store the IRQ number in the
struct rcar_dmac_chan so that it can be used later.
Signed-off-by: NNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>