Fix liquidv1 sync

A single field wasn't given a positive value which
meant it considers no peg-ins to be valid.

src/chainparams.cpp

@@ -725,6 +725,9 @@ public:
 
         g_con_blockheightinheader = true;
         g_con_elementsmode = true;
+        // TODO: Pick appropriate value for this network.
+        consensus.total_valid_epochs = 2;
+
 
         consensus.genesis_subsidy = 0;