[media] smipcie: use add_i2c_client and del_i2c_client functions

v2:
-no change, just resend with other patches.

"add_i2c_client" and "del_i2c_client" functions make code shorter and easy to maintain.

Signed-off-by: Nibble Max <nibble.max@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>