dmaengine: xilinx_dma: Add support for residue on direct AXIDMA S2MM

dmaengine: xilinx_dma: Add support for residue on direct AXIDMA S2MM

AXIDMA IP supports reporting the amount of bytes transferred on the S2MM
channel in direct mode (i.e. non-SG), but the driver does not. Thus the
driver always reports that all of the buffer was filled.

Add xilinx_dma_get_residue_axidma_direct_s2mm() which gets the residue
amount for direct AXIDMA for S2MM direction.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Suraj Gupta <suraj.gupta2@amd.com>
Link: https://patch.msgid.link/20251218-xilinx-dma-residue-fix-v1-1-7cd221d69d6b@ideasonboard.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>