media: vim2m: Remove compilation conditional to CONFIG_MEDIA_CONTROLLER

MEDIA_CONTROLLER is selected for vim2m already since commit 016baa59
("media: Kconfig: Don't expose the Request API option"). Also remove the
related #ifdefs.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>