dmaengine: Replace zero-length array with flexible-array

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

drivers/dma/timb_dma.c

@@ -88,7 +88,7 @@ struct timb_dma {
 	struct dma_device	dma;
 	void __iomem		*membase;
 	struct tasklet_struct	tasklet;
-	struct timb_dma_chan	channels[0];
+	struct timb_dma_chan	channels[];
 };
 
 static struct device *chan2dev(struct dma_chan *chan)