V4L/DVB (11843): ir-kbd-i2c: Don't use i2c_client.name for our own needs

In the standard device driver binding model, the name field of
struct i2c_client is used to match devices to their drivers, so we
must stop using it for internal purposes. Define a separate field
in struct IR_i2c as a replacement, and use it.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>