p2p: refactor: tidy up PeerManagerImpl::Misbehaving(...)

- introduce constant variables `score_before` and
  `score_after` in order to improve readability
- deduplicate calls to LogPrint(), eliminates else-branch

Author: theStack

src/net_processing.cpp

@@ -1280,14 +1280,20 @@ void PeerManagerImpl::Misbehaving(const NodeId pnode, const int howmuch, const s
     if (peer == nullptr) return;
 
     LOCK(peer->m_misbehavior_mutex);
+    const int score_before{peer->m_misbehavior_score};
     peer->m_misbehavior_score += howmuch;
+    const int score_now{peer->m_misbehavior_score};
+
     const std::string message_prefixed = message.empty() ? "" : (": " + message);
-    if (peer->m_misbehavior_score >= DISCOURAGEMENT_THRESHOLD && peer->m_misbehavior_score - howmuch < DISCOURAGEMENT_THRESHOLD) {
-        LogPrint(BCLog::NET, "Misbehaving: peer=%d (%d -> %d) DISCOURAGE THRESHOLD EXCEEDED%s\n", pnode, peer->m_misbehavior_score - howmuch, peer->m_misbehavior_score, message_prefixed);
+    std::string warning;
+
+    if (score_now >= DISCOURAGEMENT_THRESHOLD && score_before < DISCOURAGEMENT_THRESHOLD) {
+        warning = " DISCOURAGE THRESHOLD EXCEEDED";
         peer->m_should_discourage = true;
-    } else {
-        LogPrint(BCLog::NET, "Misbehaving: peer=%d (%d -> %d)%s\n", pnode, peer->m_misbehavior_score - howmuch, peer->m_misbehavior_score, message_prefixed);
     }
+
+    LogPrint(BCLog::NET, "Misbehaving: peer=%d (%d -> %d)%s%s\n",
+             pnode, score_before, score_now, warning, message_prefixed);
 }
 
 bool PeerManagerImpl::MaybePunishNodeForBlock(NodeId nodeid, const BlockValidationState& state,