media: vpss: clean up resources in init

If platform_driver_register() fails within vpss_init() resources are not
cleaned up. The patch fixes this issue by introducing the corresponding
error handling.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Evgeny Novikov <novikov@ispras.ru>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>