dmaengine: increment privatecnt when using dma_get_any_slave_channel

Channels allocated via dma_get_any_slave_channel were not increasing
the counter tracking private allocations.  When these channels were
released, privatecnt may erroneously fall to zero.  The DMA device
would then lose its DMA_PRIVATE cap and fail to allocate future private
channels (via private_candidate) as any allocations still outstanding
would incorrectly be seen as public allocations.
Signed-off-by: Christopher Freeman <cfreeman@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/dmaengine.c

@@ -571,11 +571,15 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
 
 	chan = private_candidate(&mask, device, NULL, NULL);
 	if (chan) {
+		dma_cap_set(DMA_PRIVATE, device->cap_mask);
+		device->privatecnt++;
 		err = dma_chan_get(chan);
 		if (err) {
 			pr_debug("%s: failed to get %s: (%d)\n",
 				__func__, dma_chan_name(chan), err);
 			chan = NULL;
+			if (--device->privatecnt == 0)
+				dma_cap_clear(DMA_PRIVATE, device->cap_mask);
 		}
 	}