[media] media: sh-mobile-ceu-camera: runtime PM suspending doesn't have to be synchronous

In both error and clean up cases there is no need to wait for runtime PM
to finish suspending the device.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>