udev-node: save information about device node and priority in symlink

udev-node: save information about device node and priority in symlink

Previously, we only store device IDs in /run/udev/links, and when
creating/removing device node symlink, we create sd_device object
corresponds to the IDs and read device node and priority from the
object. That requires parsing uevent and udev database files.

This makes link_find_prioritized() get the most prioritzed device node
without parsing the files.

(cherry picked from commit 377a83f0d80376456d9be203796f66f543a8b943)

Gbp-Pq: Name udev-node-save-information-about-device-node-and-priority.patch