lldpd: bump version to 1.0.18

lldpd: bump version to 1.0.18

Changes (breaking):
- Remove support for building 802.3bt TLVs (broken).

Fix:
- Fix memory leaks in EDP/FDP decoding when receiving some TLVs twice.
- Do not set interface description continuously.
- Use a different Netlink socket for changes and queries.

Signed-off-by: Sebastian Pflieger <sebastian@pflieger.email>
Link: https://github.com/openwrt/openwrt/pull/17570
Signed-off-by: Robert Marko <robimarko@gmail.com>
(cherry picked from commit a18385041eaeaf6d98ab79a30ce5fba4e712b765)