media: coda: remove redundant null pointer check before of_node_put

of_node_put has taken the null pointer check into account. So it is
safe to remove the duplicated check before of_node_put.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>