dm: Use access methods for dev/uclass private data

Most drivers use these access methods but a few do not. Update them.

In some cases the access is not permitted, so mark those with a FIXME tag
for the maintainer to check.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Pratyush Yadav <p.yadav@ti.com>
diff --git a/drivers/timer/timer-uclass.c b/drivers/timer/timer-uclass.c
index ab53555..8e63c17 100644
--- a/drivers/timer/timer-uclass.c
+++ b/drivers/timer/timer-uclass.c
@@ -40,7 +40,7 @@
 
 unsigned long notrace timer_get_rate(struct udevice *dev)
 {
-	struct timer_dev_priv *uc_priv = dev->uclass_priv;
+	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
 
 	return uc_priv->clock_rate;
 }