[media] em28xx: move sub-module data structs to a common place in the main struct

struct em28xx {

	struct kref ref;

	/* Sub-module data */

	struct em28xx_dvb *dvb;

	struct em28xx_audio adev;

	struct em28xx_IR *ir;

	/* generic device properties */

	char name[30];		/* name (including minor) of the device */

	int model;		/* index in the device_data struct */

	struct em28xx_fmt *format;

	struct em28xx_IR *ir;

	/* Some older em28xx chips needs a waiting time after writing */

	unsigned int wait_after_write;

	unsigned long i2c_hash;	/* i2c devicelist hash -

				   for boards with generic ID */

	struct em28xx_audio adev;

	/* capture state tracking */

	int capture_type;

	unsigned char top_field:1;

	/* Snapshot button input device */

	char snapshot_button_path[30];	/* path of the input dev */

	struct input_dev *sbutton_input_dev;

	struct em28xx_dvb *dvb;

};

#define kref_to_dev(d) container_of(d, struct em28xx, ref)