cleanup: use standard Golang errors package

"github.com/pkg/errors" does not offer more functionlity than that we
need from the standard "errors" package. With Golang v1.13 errors can be
wrapped with `fmt.Errorf("... %w", err)`. `errors.Is()` and
`errors.As()` are available as well.

See-also: https://tip.golang.org/doc/go1.13#error_wrapping
Signed-off-by: Niels de Vos <ndevos@redhat.com>

internal/journal/voljournal.go

@@ -20,13 +20,13 @@ import (
 	"context"
 	"encoding/binary"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"strings"
 
 	"github.com/ceph/ceph-csi/internal/util"
 
 	"github.com/pborman/uuid"
-	"github.com/pkg/errors"
 	"k8s.io/klog"
 )