media: coda: Fix runtime PM imbalance in coda_probe

When coda_firmware_request() returns an error code,
a pairing runtime PM usage counter decrement is needed
to keep the counter balanced.

Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>