[#392] ir: Remove bitsize from IR indices

There is no need to specify that IR indices are 32 bits in size.

Change return types of `Indexer` interface methods in audit and alphabet
packages. Support interface changes in `Server` implementation.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/innerring/processors/alphabet/process_emit.go

@@ -15,9 +15,9 @@ func (np *Processor) processEmit() {
 		np.log.Info("passive mode, ignore gas emission event")
 
 		return
-	} else if int(index) >= len(np.alphabetContracts) {
+	} else if index >= len(np.alphabetContracts) {
 		np.log.Debug("node is out of alphabet range, ignore gas emission event",
-			zap.Int32("index", index))
+			zap.Int("index", index))
 
 		return
 	}

pkg/innerring/processors/alphabet/processor.go

@@ -12,7 +12,7 @@ import (
 type (
 	// Indexer is a callback interface for inner ring global state.
 	Indexer interface {
-		Index() int32
+		Index() int
 	}
 
 	// Processor of events produced for alphabet contracts in sidechain.

pkg/innerring/processors/audit/processor.go

@@ -20,8 +20,8 @@ import (
 type (
 	// Indexer is a callback interface for inner ring global state.
 	Indexer interface {
-		Index() int32
-		InnerRingSize() int32
+		Index() int
+		InnerRingSize() int
 	}
 
 	// NeoFSClientCache is an interface for cache of neofs RPC clients

pkg/innerring/state.go

@@ -25,14 +25,14 @@ func (s *Server) IsActive() bool {
 
 // Index is a getter for a global index of node in inner ring list. Negative
 // index means that node is not in the inner ring list.
-func (s *Server) Index() int32 {
-	return s.innerRingIndex.Load()
+func (s *Server) Index() int {
+	return int(s.innerRingIndex.Load())
 }
 
 // InnerRingSize is a getter for a global size of inner ring list. This value
 // paired with inner ring index.
-func (s *Server) InnerRingSize() int32 {
-	return s.innerRingSize.Load()
+func (s *Server) InnerRingSize() int {
+	return int(s.innerRingSize.Load())
 }
 
 func (s *Server) voteForSidechainValidator(validators []keys.PublicKey) error {