gpu: host1x: bus: Add missing of_node_put()

for_each_child_of_node() performs an of_node_get() on each iteration, so
to break out of the loop an of_node_put() is required.

Found using Coccinelle. The semantic patch used for this is as follows:

// <smpl>
@@
expression e;
local idexpression n;
@@

 for_each_child_of_node(..., n) {
   ... when != of_node_put(n)
       when != e = n
(
   return n;
|
+  of_node_put(n);
?  return ...;
)
   ...
 }
// </smpl>

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>