davinci: Correct return value of edma_alloc_channel api

Currently, edma_alloc_channel api is returning the channel
number without prepending the controller on which the
channel was allocated. So, if a channel is allocated on
2nd controller, calls subsequent to edma_alloc_channel would
never know that channel was allocated on the 2nd controller,
and continue to operate on 1st controller, resulting in edma
failure. This patch fixes this issue.
Signed-off-by: NSudhakar Rajashekhara <sudhakar.raj@ti.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-davinci/dma.c

@@ -642,7 +642,7 @@ int edma_alloc_channel(int channel,
 
 	map_dmach_queue(ctlr, channel, eventq_no);
 
-	return channel;
+	return EDMA_CTLR_CHAN(ctlr, channel);
 }
 EXPORT_SYMBOL(edma_alloc_channel);