Fix dmaengine_submit() return type

desc->tx_submit's return type is dma_cookie_t, not int.  Therefore,
dmaengine_submit() should match this return type as it's just
wrapping this detail.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

include/linux/dmaengine.h

@@ -532,7 +532,7 @@ static inline int dmaengine_resume(struct dma_chan *chan)
 	return dmaengine_device_control(chan, DMA_RESUME, 0);
 }
 
-static inline int dmaengine_submit(struct dma_async_tx_descriptor *desc)
+static inline dma_cookie_t dmaengine_submit(struct dma_async_tx_descriptor *desc)
 {
 	return desc->tx_submit(desc);
 }