dmaengine: idxd: set DMA_INTERRUPT cap bit

Even though idxd driver has always supported interrupt, it never actually
set the DMA_INTERRUPT cap bit. Rectify this mistake so the interrupt
capability is advertised.

Reported-by: Ben Walker <benjamin.walker@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/164971497859.2201379.17925303210723708961.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/idxd/dma.c

@@ -193,6 +193,7 @@ int idxd_register_dma_device(struct idxd_device *idxd)
 	INIT_LIST_HEAD(&dma->channels);
 	dma->dev = dev;
 
+	dma_cap_set(DMA_INTERRUPT, dma->cap_mask);
 	dma_cap_set(DMA_PRIVATE, dma->cap_mask);
 	dma_cap_set(DMA_COMPLETION_NO_ORDER, dma->cap_mask);
 	dma->device_release = idxd_dma_release;