edma_alloc_channel() bugfix

Bugfix to the EDMA "allocate a channel with no peripheral event"
code path:  consult the right bitmap, in the right way.  Such
channels are useful for chaining, manual triggering, and QDMA.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-davinci/dma.c

@@ -485,7 +485,7 @@ int edma_alloc_channel(int channel,
 	if (channel < 0) {
 		channel = 0;
 		for (;;) {
-			channel = find_next_zero_bit(edma_inuse,
+			channel = find_next_bit(edma_noevent,
 					num_channels, channel);
 			if (channel == num_channels)
 				return -ENOMEM;