media: usb: dvb-usb-v2: rtl28xxu: convert to use i2c_new_client_device()

Use the newer API returning an ERRPTR and use the new helper to bail
out.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>