Codechange: do not use MallocT for the pool

Needed to make the placement new operator use Tindex over size_t because of
ambiguity for the delete operator variant that also has the size.

src/saveload/autoreplace_sl.cpp

@@ -45,7 +45,7 @@ struct ERNWChunkHandler : ChunkHandler {
 		int index;
 
 		while ((index = SlIterateArray()) != -1) {
-			EngineRenew *er = new (index) EngineRenew();
+			EngineRenew *er = new (EngineRenewID(index)) EngineRenew();
 			SlObject(er, slt);
 
 			/* Advanced vehicle lists, ungrouped vehicles got added */