message: refactor: Use Mutex type for g_cs_recent_confirmed_transactions
diff: @@ -191,7 +191,7 @@ namespace {
  * We use this to avoid requesting transactions that have already been
  * confirnmed.
  */
  - RecursiveMutex g_cs_recent_confirmed_transactions;
  + Mutex g_cs_recent_confirmed_transactions;
  std::unique_ptr<CRollingBloomFilter> g_recent_confirmed_transactions GUARDED_BY(g_cs_recent_confirmed_transactions);
  /** Blocks that are in flight, and that are in the queue to be downloaded. */
  