ARM: sa11x0: fix build errors from DMA engine API updates

The recent merge of the sa11x0 code into mainline had silent conflicts
with further development of the DMA engine API, leading to build errors
and warnings:

drivers/net/irda/sa1100_ir.c: In function 'sa1100_irda_dma_start':
drivers/net/irda/sa1100_ir.c:151: error: too few arguments to function 'chan->device->device_prep_slave_sg'
drivers/dma/sa11x0-dma.c: In function 'sa11x0_dma_probe':
drivers/dma/sa11x0-dma.c:950: warning: assignment from incompatible pointer type

Fix these.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/dma/sa11x0-dma.c

@@ -585,7 +585,7 @@ static dma_cookie_t sa11x0_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 
 static struct dma_async_tx_descriptor *sa11x0_dma_prep_slave_sg(
 	struct dma_chan *chan, struct scatterlist *sg, unsigned int sglen,
-	enum dma_transfer_direction dir, unsigned long flags)
+	enum dma_transfer_direction dir, unsigned long flags, void *context)
 {
 	struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan);
 	struct sa11x0_dma_desc *txd;

drivers/net/irda/sa1100_ir.c

@@ -147,7 +147,7 @@ static void sa1100_irda_dma_start(struct sa1100_buf *buf,
 	struct dma_async_tx_descriptor *desc;
 	struct dma_chan *chan = buf->chan;
 
-	desc = chan->device->device_prep_slave_sg(chan, &buf->sg, 1, dir,
+	desc = dmaengine_prep_slave_sg(chan, &buf->sg, 1, dir,
 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (desc) {
 		desc->callback = cb;