stdio: Pass device pointer to stdio methods

At present stdio device functions do not get any clue as to which stdio
device is being acted on. Some implementations go to great lengths to work
around this, such as defining a whole separate set of functions for each
possible device.

For driver model we need to associate a stdio_dev with a device. It doesn't
seem possible to continue with this work-around approach.

Instead, add a stdio_dev pointer to each of the stdio member functions.

Note: The serial drivers have the same problem, but it is not strictly
necessary to fix that to get driver model running. Also, if we convert
serial over to driver model the problem will go away.

Code size increases by 244 bytes for Thumb2 and 428 for PowerPC.

22: stdio: Pass device pointer to stdio methods
       arm: (for 2/2 boards)  all +244.0  bss -4.0  text +248.0
   powerpc: (for 1/1 boards)  all +428.0  text +428.0

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Marek Vasut <marex@denx.de>
Reviewed-by: Marek Vasut <marex@denx.de>
diff --git a/drivers/input/cros_ec_keyb.c b/drivers/input/cros_ec_keyb.c
index a2501e0..47502b1 100644
--- a/drivers/input/cros_ec_keyb.c
+++ b/drivers/input/cros_ec_keyb.c
@@ -93,7 +93,7 @@
  *
  * @return 0 if no keys available, 1 if keys are available
  */
-static int kbd_tstc(void)
+static int kbd_tstc(struct stdio_dev *dev)
 {
 	/* Just get input to do this for us */
 	return config.inited ? input_tstc(&config.input) : 0;
@@ -104,7 +104,7 @@
  *
  * @return ASCII key code, or 0 if no key, or -1 if error
  */
-static int kbd_getc(void)
+static int kbd_getc(struct stdio_dev *dev)
 {
 	/* Just get input to do this for us */
 	return config.inited ? input_getc(&config.input) : 0;
@@ -214,7 +214,7 @@
  *
  * @return 0 if ok, -1 on error
  */
-static int cros_ec_init_keyboard(void)
+static int cros_ec_init_keyboard(struct stdio_dev *dev)
 {
 	const void *blob = gd->fdt_blob;
 	int node;