Input: synaptics-rmi4 - use of_get_child_by_name() to fix refcount

Calling of_find_node_by_name() assumes that the caller has incremented
the refcount of the of_node being passed in. Currently, the caller is
not incrementing the refcount of the of_node which results in the node
being prematurely freed when of_find_node_by_name() calls of_node_put()
on it. Instead use of_get_child_by_name() which does not call put on the
of_node.

Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/rmi4/rmi_bus.c b/drivers/input/rmi4/rmi_bus.c
index b368b05..253df96 100644
--- a/drivers/input/rmi4/rmi_bus.c
+++ b/drivers/input/rmi4/rmi_bus.c
@@ -157,11 +157,11 @@
 static void rmi_function_of_probe(struct rmi_function *fn)
 {
 	char of_name[9];
+	struct device_node *node = fn->rmi_dev->xport->dev->of_node;
 
 	snprintf(of_name, sizeof(of_name), "rmi4-f%02x",
 		fn->fd.function_number);
-	fn->dev.of_node = of_find_node_by_name(
-				fn->rmi_dev->xport->dev->of_node, of_name);
+	fn->dev.of_node = of_get_child_by_name(node, of_name);
 }
 #else
 static inline void rmi_function_of_probe(struct rmi_function *fn)