dm: Avoid accessing seq directly

At present various drivers etc. access the device's 'seq' member directly.
This makes it harder to change the meaning of that member. Change access
to go through a function instead.

The drivers/i2c/lpc32xx_i2c.c file is left unchanged for now.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/watchdog/orion_wdt.c b/drivers/watchdog/orion_wdt.c
index 35e25d4..167af90 100644
--- a/drivers/watchdog/orion_wdt.c
+++ b/drivers/watchdog/orion_wdt.c
@@ -158,7 +158,7 @@
 	struct orion_wdt_priv *priv = dev_get_priv(dev);
 	int ret;
 
-	debug("%s: Probing wdt%u\n", __func__, dev->seq);
+	debug("%s: Probing wdt%u\n", __func__, dev_seq(dev));
 	orion_wdt_stop(dev);
 
 	ret = clk_get_by_name(dev, "fixed", &priv->clk);