dm: Rename dev_get_parentdata() to dev_get_parent_priv()

The current name is inconsistent with other driver model data access
functions. Rename it and fix up all users.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/include/spi.h b/include/spi.h
index 51fdfd6..b4d2723 100644
--- a/include/spi.h
+++ b/include/spi.h
@@ -88,7 +88,7 @@
  * struct spi_slave - Representation of a SPI slave
  *
  * For driver model this is the per-child data used by the SPI bus. It can
- * be accessed using dev_get_parentdata() on the slave device. The SPI uclass
+ * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass
  * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the
  * driver should not override it. Two platform data fields (max_hz and mode)
  * are copied into this structure to provide an initial value. This allows