[#622] pkg/innerring: Add composite validator

Add `CompositeValidator` that wraps
`netmap.NodeValidator`s and implements
`NodeValidator` interface itself.

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>

pkg/innerring/processors/netmap/nodevalidation/validator.go

@@ -0,0 +1,37 @@
+package nodevalidation
+
+import (
+	apinetmap "github.com/nspcc-dev/neofs-api-go/pkg/netmap"
+	"github.com/nspcc-dev/neofs-node/pkg/innerring/processors/netmap"
+)
+
+// CompositeValidator wraps `netmap.NodeValidator`s.
+//
+// For correct operation, CompositeValidator must be created
+// using the constructor (New). After successful creation,
+// the CompositeValidator is immediately ready to work through
+// API.
+type CompositeValidator struct {
+	validators []netmap.NodeValidator
+}
+
+// New creates a new instance of the CompositeValidator.
+//
+// The created CompositeValidator does not require additional
+// initialization and is completely ready for work.
+func New(validators ...netmap.NodeValidator) *CompositeValidator {
+	return &CompositeValidator{validators}
+}
+
+// VerifyAndUpdate passes apinetmap.NodeInfo to wrapped validators.
+//
+// If error appears, returns it immediately.
+func (c *CompositeValidator) VerifyAndUpdate(ni *apinetmap.NodeInfo) error {
+	for _, v := range c.validators {
+		if err := v.VerifyAndUpdate(ni); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}