media: ccs: Rename ccs_create_subdev as ccs_init_subdev

The ccs_create_subdev() function initialises a sub-device in the CCS
driver, including CCS specific needs. Rename it as ccs_init_subdev() as it
better reflects what the function does.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>