udev-node: use symlink_atomic_full_label() to create devlink

udev-node: use symlink_atomic_full_label() to create devlink

If the filename of a device symlink is too long, then the temporary
filename may become invalid, and we fail to create symlink.

The function `tempfn_random()` used in symlink_atomic_full() generates
a safe temporary filename.

Note that, thanks to the PR #23043, now only one worker can handle
the same symlink simultaneously. Hence, the device ID based temporary
filename is not necessary.