media: i2c: imx334: Use subdev state lock for synchronization

media: i2c: imx334: Use subdev state lock for synchronization

Replace the custom mutex in the imx334 driver with the V4L2 subdev state
lock for control synchronization. Initialize the subdev with
v4l2_subdev_init_finalize in imx334_probe, adding proper cleanup in error
paths and imx334_remove. This aligns the driver with V4L2 standards.

Signed-off-by: Tarang Raval <tarang.raval@siliconsignals.io>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>