Use LOG_TARGET in consensus related crates (#12875)

* Use shared LOG_TARGET in consensus related crates
* Rename target from "afg" to "grandpa"

substrate/client/consensus/aura/src/import_queue.rs

@@ -20,6 +20,7 @@
 
 use crate::{
 	aura_err, authorities, find_pre_digest, slot_author, AuthorityId, CompatibilityMode, Error,
+	LOG_TARGET,
 };
 use codec::{Codec, Decode, Encode};
 use log::{debug, info, trace};
@@ -88,7 +89,7 @@ where
 						.map_err(Error::Client)?
 				{
 					info!(
-						target: "aura",
+						target: LOG_TARGET,
 						"Slot author is equivocating at slot {} with headers {:?} and {:?}",
 						slot,
 						equivocation_proof.first_header.hash(),
@@ -256,7 +257,7 @@ where
 					block.body = Some(inner_body);
 				}
 
-				trace!(target: "aura", "Checked {:?}; importing.", pre_header);
+				trace!(target: LOG_TARGET, "Checked {:?}; importing.", pre_header);
 				telemetry!(
 					self.telemetry;
 					CONSENSUS_TRACE;
@@ -272,7 +273,7 @@ where
 				Ok((block, None))
 			},
 			CheckedHeader::Deferred(a, b) => {
-				debug!(target: "aura", "Checking {:?} failed; {:?}, {:?}.", hash, a, b);
+				debug!(target: LOG_TARGET, "Checking {:?} failed; {:?}, {:?}.", hash, a, b);
 				telemetry!(
 					self.telemetry;
 					CONSENSUS_DEBUG;

substrate/client/consensus/aura/src/lib.rs

@@ -72,6 +72,8 @@ pub use sp_consensus_aura::{
 	AuraApi, ConsensusLog, SlotDuration, AURA_ENGINE_ID,
 };
 
+const LOG_TARGET: &str = "aura";
+
 type AuthorityId<P> = <P as Pair>::Public;
 
 /// Run `AURA` in a compatibility mode.
@@ -530,7 +532,7 @@ where
 }
 
 fn aura_err<B: BlockT>(error: Error<B>) -> Error<B> {
-	debug!(target: "aura", "{}", error);
+	debug!(target: LOG_TARGET, "{}", error);
 	error
 }
 
@@ -580,10 +582,10 @@ pub fn find_pre_digest<B: BlockT, Signature: Codec>(header: &B::Header) -> Resul
 
 	let mut pre_digest: Option<Slot> = None;
 	for log in header.digest().logs() {
-		trace!(target: "aura", "Checking log {:?}", log);
+		trace!(target: LOG_TARGET, "Checking log {:?}", log);
 		match (CompatibleDigestItem::<Signature>::as_aura_pre_digest(log), pre_digest.is_some()) {
 			(Some(_), true) => return Err(aura_err(Error::MultipleHeaders)),
-			(None, _) => trace!(target: "aura", "Ignoring digest not meant for us"),
+			(None, _) => trace!(target: LOG_TARGET, "Ignoring digest not meant for us"),
 			(s, false) => pre_digest = s,
 		}
 	}