mining: Use test net block ver on simnet.

This modifies the mining code to produce blocks on the simulation
network with the same block version as other test networks as opposed to
the block version used on the main network.

internal/mining/mining.go

@@ -267,7 +267,7 @@ const (
 	generatedBlockVersion = 9
 
 	// generatedBlockVersionTest is the version of the block being generated
-	// for networks other than the main and simulation networks.
+	// for networks other than the main network.
 	generatedBlockVersionTest = 10
 
 	// blockHeaderOverhead is the max number of bytes it takes to serialize
@@ -2296,9 +2296,7 @@ nextPriorityQueueItem:
 
 	// Choose the block version to generate based on the network.
 	blockVersion := int32(generatedBlockVersion)
-	if g.cfg.ChainParams.Net != wire.MainNet &&
-		g.cfg.ChainParams.Net != wire.SimNet {
-
+	if g.cfg.ChainParams.Net != wire.MainNet {
 		blockVersion = generatedBlockVersionTest
 	}