sh: dma: fix request_irq usage

When calling request_irq with IRQF_SHARED, the dev cookie must be set
(i.e. non-NULL), otherwise the code rejects it immediately with -EINVAL.
So restore the logic here where we'd pass a pointer to the name as a
dummy unique val.

Otherwise, booting up on my LANDISK system would fail with:
	DMAC Address Error0 request_irq fail

This was introduced in commit 7f47c718.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/drivers/dma/dma-sh.c

@@ -335,7 +335,7 @@ static int dmae_irq_init(void)
 
 	for (n = 0; n < NR_DMAE; n++) {
 		int i = request_irq(get_dma_error_irq(n), dma_err,
-				    IRQF_SHARED, dmae_name[n], NULL);
+				    IRQF_SHARED, dmae_name[n], (void *)dmae_name[n]);
 		if (unlikely(i < 0)) {
 			printk(KERN_ERR "%s request_irq fail\n", dmae_name[n]);
 			return i;