dmaengine: omap-dma: Add memory barrier to dma_resume path

Add mb() call to resume path to ensure the necessary barrier.
Resume can happen after waking up from suspend for example.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/omap-dma.c

@@ -1017,6 +1017,8 @@ static int omap_dma_resume(struct omap_chan *c)
 		return -EINVAL;
 
 	if (c->paused) {
+		mb();
+
 		omap_dma_start(c, c->desc);
 		c->paused = false;
 	}