media: Update Intel-submitted camera sensor driver contacts

Hyungwoo's e-mail no longer works so I presume he's left the company. Drop
Hyungwoo as maintainer on ov5670 driver and remove his e-mail from other
sensor drivers.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>