dmaengine: sh: rz-dmac: Add cyclic DMA support

dmaengine: sh: rz-dmac: Add cyclic DMA support

Add cyclic DMA support to the RZ DMAC driver. A per-channel status bit is
introduced to mark cyclic channels and is set during the DMA prepare
callback. The IRQ handler checks this status bit and calls
vchan_cyclic_callback() accordingly.

Tested-by: John Madieu <john.madieu.xa@bp.renesas.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Tested-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
Link: https://patch.msgid.link/20260526084710.3491480-13-claudiu.beznea@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>