Bail out if registers can not be updated.

Addresses-Coverity-ID: 1461655 ("Code maintainability issues")

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Fixes: e6089fec ("media: m88ds3103: Add support for ds3103b demod")
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>