Replace exit(1) on every failure path with return null so callers that
iterate over multiple radios can collect results from the radios that
did succeed instead of aborting on the first one that refuses an
off-channel scan.
Route diagnostics to stderr via warn() so stdout stays clean for
callers parsing JSON output, and include the device name in each
message to disambiguate per-radio failures.
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
0c2fb39c5a