dmaengine: bam-dma: fix a warning about missing capabilities

Avoid the warning below triggered during dmaengine async device
registration.

WARNING: CPU: 1 PID: 1 at linux/drivers/dma/dmaengine.c:863
dma_async_device_register+0x2a8/0x4b8()
this driver doesn't support generic slave capabilities reporting

To do that fill mandatory .directions bit mask,
.src/dst_addr_widths and .residue_granularity dma_device fields
with appropriate values.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/qcom_bam_dma.c b/drivers/dma/qcom_bam_dma.c
index d7a33b3..d9f1a18 100644
--- a/drivers/dma/qcom_bam_dma.c
+++ b/drivers/dma/qcom_bam_dma.c
@@ -1143,6 +1143,10 @@
 	dma_cap_set(DMA_SLAVE, bdev->common.cap_mask);
 
 	/* initialize dmaengine apis */
+	bdev->common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+	bdev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
+	bdev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	bdev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
 	bdev->common.device_alloc_chan_resources = bam_alloc_chan;
 	bdev->common.device_free_chan_resources = bam_free_chan;
 	bdev->common.device_prep_slave_sg = bam_prep_slave_sg;