net_processing: Add review-only assertion to PeerManager

src/net_processing.cpp

@@ -1245,6 +1245,7 @@ PeerManagerImpl::PeerManagerImpl(const CChainParams& chainparams, CConnman& conn
       m_stale_tip_check_time(0),
       m_ignore_incoming_txs(ignore_incoming_txs)
 {
+    assert(std::addressof(g_chainman) == std::addressof(m_chainman));
     // Initialize global variables that cannot be constructed at startup.
     recentRejects.reset(new CRollingBloomFilter(120000, 0.000001));