libs/bits: inline defer and change order of mutexes (#5187)

* libs/bits: inline defer and change order of mutexes

Closes #3217

* abci/client: unexpose StopForError func

a) it's not called outside
b) the reason for exposing it in the first place is unclear
c) Stop already exist if someone from outside wants to stop the client

libs/bits/bit_array.go

@@ -355,14 +355,12 @@ func (bA *BitArray) Update(o *BitArray) {
 	if bA == nil || o == nil {
 		return
 	}
+
 	bA.mtx.Lock()
 	o.mtx.Lock()
-	defer func() {
-		bA.mtx.Unlock()
-		o.mtx.Unlock()
-	}()
-
 	copy(bA.Elems, o.Elems)
+	o.mtx.Unlock()
+	bA.mtx.Unlock()
 }
 
 // MarshalJSON implements json.Marshaler interface by marshaling bit array