rebase: update github.com/ceph/go-ceph to master

this commit updates the version of go-ceph imported to
latest, so we can make use of github.com/ceph/go-ceph/cephfs

Signed-off-by: Riya Singhal <rsinghal@redhat.com>

vendor/github.com/ceph/go-ceph/cephfs/errors.go

@@ -0,0 +1,67 @@
+package cephfs
+
+/*
+#include <errno.h>
+*/
+import "C"
+
+import (
+	"errors"
+
+	"github.com/ceph/go-ceph/internal/errutil"
+)
+
+// cephFSError represents an error condition returned from the CephFS APIs.
+type cephFSError int
+
+// Error returns the error string for the cephFSError type.
+func (e cephFSError) Error() string {
+	return errutil.FormatErrorCode("cephfs", int(e))
+}
+
+func (e cephFSError) ErrorCode() int {
+	return int(e)
+}
+
+func getError(e C.int) error {
+	if e == 0 {
+		return nil
+	}
+	return cephFSError(e)
+}
+
+// getErrorIfNegative converts a ceph return code to error if negative.
+// This is useful for functions that return a usable positive value on
+// success but a negative error number on error.
+func getErrorIfNegative(ret C.int) error {
+	if ret >= 0 {
+		return nil
+	}
+	return getError(ret)
+}
+
+// Public go errors:
+
+var (
+	// ErrEmptyArgument may be returned if a function argument is passed
+	// a zero-length slice or map.
+	ErrEmptyArgument = errors.New("Argument must contain at least one item")
+)
+
+// Public CephFSErrors:
+
+const (
+	// ErrNotConnected may be returned when client is not connected
+	// to a cluster.
+	ErrNotConnected = cephFSError(-C.ENOTCONN)
+	// ErrNotExist indicates a non-specific missing resource.
+	ErrNotExist = cephFSError(-C.ENOENT)
+)
+
+// Private errors:
+
+const (
+	errInvalid     = cephFSError(-C.EINVAL)
+	errNameTooLong = cephFSError(-C.ENAMETOOLONG)
+	errRange       = cephFSError(-C.ERANGE)
+)