tda18271_lookup_map() may return negative error code, but
tda18271c2_rf_tracking_filters_correction() doesn't check it
as the other callers.
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
Signed-off-by: Karina Yankevich <k.yankevich@omp.ru>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>