media: staging: media: imx: change imx_media_fim_set_stream() to return void

At present, the function imx_media_fim_set_stream() always returns 0.
So, convert it to be a function returning void instead. Issue identified
using the returnvar.cocci Coccinelle semantic patch.

Signed-off-by: Deepak R Varma <drv@mailo.com>
Reviewed-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>