Input: st1232 - note that the receive buffer is DMA-safe

The receiving buffer is allocated separately from the main driver
data structure, and is naturally DMA-safe, so mark it as such when
building I2C transfer message.
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/st1232.c

@@ -66,7 +66,7 @@ static int st1232_ts_read_data(struct st1232_ts_data *ts)
 		},
 		{
 			.addr	= client->addr,
-			.flags	= I2C_M_RD,
+			.flags	= I2C_M_RD | I2C_M_DMA_SAFE,
 			.len	= ts->read_buf_len,
 			.buf	= ts->read_buf,
 		}