serial: sh-sci: fix compilation breakage, when DMA is enabled

A recent commit:

commit d6fa5a4e
Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
    serial: sh-sci: prepare for conversion to the shdma base library

is not sufficient to update the sh-sci driver to the new shdma driver
layout. This caused compilation breakage, when CONFIG_SERIAL_SH_SCI_DMA
is enabled. This patch trivially fixes the problem by updating the DMA
descriptor manipulation code.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

drivers/tty/serial/sh-sci.c

@@ -25,6 +25,7 @@
 
 #include <linux/module.h>
 #include <linux/errno.h>
+#include <linux/sh_dma.h>
 #include <linux/timer.h>
 #include <linux/interrupt.h>
 #include <linux/tty.h>
@@ -1410,8 +1411,8 @@ static void work_fn_rx(struct work_struct *work)
 		/* Handle incomplete DMA receive */
 		struct tty_struct *tty = port->state->port.tty;
 		struct dma_chan *chan = s->chan_rx;
-		struct sh_desc *sh_desc = container_of(desc, struct sh_desc,
-						       async_tx);
+		struct shdma_desc *sh_desc = container_of(desc,
+					struct shdma_desc, async_tx);
 		unsigned long flags;
 		int count;