crypto: replace noarg fmt.Errorf with errors.New (ethereum#27333)

Author: gzliudan

crypto/signature_cgo.go

@@ -22,6 +22,7 @@ package crypto
 import (
 	"crypto/ecdsa"
 	"crypto/elliptic"
+	"errors"
 	"fmt"
 
 	"github.com/XinFinOrg/XDPoSChain/common/math"
@@ -72,7 +73,7 @@ func VerifySignature(pubkey, digestHash, signature []byte) bool {
 func DecompressPubkey(pubkey []byte) (*ecdsa.PublicKey, error) {
 	x, y := secp256k1.DecompressPubkey(pubkey)
 	if x == nil {
-		return nil, fmt.Errorf("invalid public key")
+		return nil, errors.New("invalid public key")
 	}
 	return &ecdsa.PublicKey{X: x, Y: y, Curve: S256()}, nil
 }

crypto/signature_nocgo.go

@@ -74,12 +74,12 @@ func Sign(hash []byte, prv *ecdsa.PrivateKey) ([]byte, error) {
 		return nil, fmt.Errorf("hash is required to be exactly 32 bytes (%d)", len(hash))
 	}
 	if prv.Curve != btcec.S256() {
-		return nil, fmt.Errorf("private key curve is not secp256k1")
+		return nil, errors.New("private key curve is not secp256k1")
 	}
 	// ecdsa.PrivateKey -> btcec.PrivateKey
 	var priv btcec.PrivateKey
 	if overflow := priv.Key.SetByteSlice(prv.D.Bytes()); overflow || priv.Key.IsZero() {
-		return nil, fmt.Errorf("invalid private key")
+		return nil, errors.New("invalid private key")
 	}
 	defer priv.Zero()
 	sig, err := btc_ecdsa.SignCompact(&priv, hash, false) // ref uncompressed pubkey