update dependencies

vendor/golang.org/x/sys/unix/syscall_dragonfly.go

@@ -234,6 +234,13 @@ func Uname(uname *Utsname) error {
 	return nil
 }
 
+func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
+	if raceenabled {
+		raceReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	return sendfile(outfd, infd, offset, count)
+}
+
 /*
  * Exposed directly
  */
@@ -297,6 +304,7 @@ func Uname(uname *Utsname) error {
 //sys	read(fd int, p []byte) (n int, err error)
 //sys	Readlink(path string, buf []byte) (n int, err error)
 //sys	Rename(from string, to string) (err error)
+//sys	Renameat(fromfd int, from string, tofd int, to string) (err error)
 //sys	Revoke(path string) (err error)
 //sys	Rmdir(path string) (err error)
 //sys	Seek(fd int, offset int64, whence int) (newoffset int64, err error) = SYS_LSEEK