[media] ad9389b/adv7604/ths8200: use new v4l2_print_dv_timings helper

These three drivers all have code to log the dv_timings contents. Replace
that code with the new helper function.

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