dmaengine: imx-sdma: Declare slave capabilities for the generic code

Since ecc19d17 ("dmaengine: Add a warning for drivers not using the
generic slave caps retrieval") the following warning is observed:

[    0.224981] ------------[ cut here ]------------
[    0.225013] WARNING: CPU: 0 PID: 1 at drivers/dma/dmaengine.c:830 dma_async_device_register+0x2a0/0x4c8()
[    0.225023] this driver doesn't support generic slave capabilities reporting

Declare the slave capabilities to avoid such warning.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/imx-sdma.c

@@ -1595,6 +1595,10 @@ static int sdma_probe(struct platform_device *pdev)
 	sdma->dma_device.device_prep_dma_cyclic = sdma_prep_dma_cyclic;
 	sdma->dma_device.device_config = sdma_config;
 	sdma->dma_device.device_terminate_all = sdma_disable_channel;
+	sdma->dma_device.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
+	sdma->dma_device.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
+	sdma->dma_device.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+	sdma->dma_device.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 	sdma->dma_device.device_issue_pending = sdma_issue_pending;
 	sdma->dma_device.dev->dma_parms = &sdma->dma_parms;
 	dma_set_max_seg_size(sdma->dma_device.dev, 65535);