i2c-designware: i2c_dw_xfer_msg can be static

i2c_dw_xfer_msg is only called internally so it can be static. It
original was, before the driver split. No idea why it was changed at
that time.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NDirk Brandewie <dirk.brandewie@gmail.com>

drivers/i2c/busses/i2c-designware-core.c

@@ -370,7 +370,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
  * messages into the tx buffer.  Even if the size of i2c_msg data is
  * longer than the size of the tx buffer, it handles everything.
  */
-void
+static void
 i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 {
 	struct i2c_msg *msgs = dev->msgs;