dmaengine: coh901318: fix function return types build warnings

A recent patch that removed coh901318_control() replaced it
with a number of pointers to existing functions, but those
unfortunately have the wrong return type and need to be
changed to return an 'int' with an error value rather than
a 'void' to avoid these build warnings:

drivers/dma/coh901318.c:2697:32: warning: assignment from incompatible pointer type
base->dma_slave.device_config = coh901318_dma_set_runtimeconfig;
^
drivers/dma/coh901318.c:2698:31: warning: assignment from incompatible pointer type
base->dma_slave.device_pause = coh901318_pause;
^
drivers/dma/coh901318.c:2699:32: warning: assignment from incompatible pointer type
base->dma_slave.device_resume = coh901318_resume

The coh901318_base_init function has the correct return type
already, but needs to be marked 'static' to avoid a sparse
warning about a missing declaration.

Signed-off-by: Arnd Bergmann <[e-mail]>
Fixes: 6782af118b6c ("dmaengine: coh901318: Split device_control")
Acked-by: Linus Walleij <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/coh901318.c

···
  * Pauses a transfer without losing data. Enables power save.
  * Use this function in conjunction with coh901318_resume.
  */
-static void coh901318_pause(struct dma_chan *chan)
+static int coh901318_pause(struct dma_chan *chan)
 {
 	u32 val;
 	unsigned long flags;
···
 	enable_powersave(cohc);
 
 	spin_unlock_irqrestore(&cohc->lock, flags);
+	return 0;
 }
 
 /* Resumes a transfer that has been stopped via 300_dma_stop(..).
    Power save is handled.
 */
-static void coh901318_resume(struct dma_chan *chan)
+static int coh901318_resume(struct dma_chan *chan)
 {
 	u32 val;
 	unsigned long flags;
···
 	}
 
 	spin_unlock_irqrestore(&cohc->lock, flags);
+	return 0;
 }
 
 bool coh901318_filter_id(struct dma_chan *chan, void *chan_id)
···
 	},
 };
 
-static void coh901318_dma_set_runtimeconfig(struct dma_chan *chan,
-			struct dma_slave_config *config)
+static int coh901318_dma_set_runtimeconfig(struct dma_chan *chan,
+					   struct dma_slave_config *config)
 {
 	struct coh901318_chan *cohc = to_coh901318_chan(chan);
 	dma_addr_t addr;
···
 		maxburst = config->dst_maxburst;
 	} else {
 		dev_err(COHC_2_DEV(cohc), "illegal channel mode\n");
-		return;
+		return -EINVAL;
 	}
 
 	dev_dbg(COHC_2_DEV(cohc), "configure channel for %d byte transfers\n",
···
 	default:
 		dev_err(COHC_2_DEV(cohc),
 			"bad runtimeconfig: alien address width\n");
-		return;
+		return -EINVAL;
 	}
 
 	ctrl |= burst_sizes[i].reg;
···
 
 	cohc->addr = addr;
 	cohc->ctrl = ctrl;
+
+	return 0;
 }
 
-void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
-			 struct coh901318_base *base)
+static void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
+				struct coh901318_base *base)
 {
 	int chans_i;
 	int i = 0;