V4L/DVB (12147): pwc: remove definitions that are already present at videodev2.h

#define DEVICE_USE_CODEC3(x) ((x)>=700)

#define DEVICE_USE_CODEC23(x) ((x)>=675)

#ifndef V4L2_PIX_FMT_PWC1

#define V4L2_PIX_FMT_PWC1	v4l2_fourcc('P','W','C','1')

#define V4L2_PIX_FMT_PWC2	v4l2_fourcc('P','W','C','2')

#endif

/* The following structures were based on cpia.h. Why reinvent the wheel? :-) */

struct pwc_iso_buf

{