Move log to tracing package

Signed-off-by: Erik Hollensbe <git@hollensbe.org>

crates/resolver/src/async_resolver.rs

@@ -19,6 +19,7 @@ use proto::rr::domain::TryParseIp;
 use proto::rr::{IntoName, Name, Record, RecordType};
 use proto::xfer::{DnsRequestOptions, RetryDnsHandle};
 use proto::DnsHandle;
+use tracing::{debug, trace};
 
 use crate::caching_client::CachingClient;
 use crate::config::{ResolverConfig, ResolverOpts};
@@ -227,7 +228,7 @@ impl<C: DnsHandle<Error = ResolveError>, P: ConnectionProvider<Conn = C>> AsyncR
             #[cfg(not(feature = "dnssec"))]
             {
                 // TODO: should this just be a panic, or a pinned error?
-                warn!("validate option is only available with 'dnssec' feature");
+                tracing::warn!("validate option is only available with 'dnssec' feature");
                 either = LookupEither::Retry(client);
             }
         } else {