of: Delete an unnecessary check before the function call "of_node_put"

The of_node_put() function tests whether its argument is NULL
and then returns immediately.
Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Rob Herring <robh@kernel.org>
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 7792266..cb255a0 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1631,8 +1631,7 @@
 	 */
 
  err:
-	if (it.node)
-		of_node_put(it.node);
+	of_node_put(it.node);
 	return rc;
 }