media: staging: media: starfive: camss: Drop obsolete return value documentation

Recently the function stfcamss_remove() was changed to not return a
value. Drop the documentation of the return value in the kernel doc.

Fixes: b1f3677a ("media: staging: media: starfive: camss: Convert to platform remove callback returning void")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>