[media] em28xx: move struct v4l2_clk *clk from struct em28xx to struct v4l2

The current clock definition applies only to the V4L2 side of the
driver. Move its struct pointer to the v4l2_dev, where it belongs.

Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --cc drivers/media/usb/em28xx/em28xx-camera.c
Simple merge

diff --cc drivers/media/usb/em28xx/em28xx-video.c
Simple merge

diff --cc drivers/media/usb/em28xx/em28xx.h
Simple merge