Fix pl08x warnings

drivers/dma/amba-pl08x.c: In function 'pl08x_desc_free':
drivers/dma/amba-pl08x.c:1173:2: warning: passing argument 1 of 'dma_descriptor_unmap' from incompatible pointer type
include/linux/dmaengine.h:476:91: note: expected 'struct dma_async_tx_descriptor *' but argument is of type 'struct pl08x_txd *'

Fixes: d38a8c622a1b ("dmaengine: prepare for generic 'unmap' data")
Signed-off-by: Russell King <[e-mail]>
Signed-off-by: Dan Williams <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/amba-pl08x.c

···
 	struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
 	struct pl08x_dma_chan *plchan = to_pl08x_chan(vd->tx.chan);
 
-	dma_descriptor_unmap(txd);
+	dma_descriptor_unmap(&vd->tx);
 	if (!txd->done)
 		pl08x_release_mux(plchan);