It should call of_node_put on non-null poiner.

Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: NPeter Chen <peter.chen@nxp.com>
Acked-by: NBenoit Parrot <bparrot@ti.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>