media: ipu3-cio2, dw9714: Remove Jian Xu's e-mail

Jian Xu has left the company. Remove his e-mail address that no longer
works.

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