lldpd: new package

lldpd is a 802.1ab implementation (LLDP) to help you locate neighbors
of all your equipments.

LLDP is an industry standard protocol designed to supplant proprietary
Link-Layer protocols such as EDP or CDP. The goal of LLDP is to
provide an inter-vendor compatible mechanism to deliver Link-Layer
notifications to adjacent network devices.

https://vincentbernat.github.io/lldpd/



[Thomas:
 - add depends on BR2_USE_MMU, since fork() is used
 - rewrap Config.in help text]

Signed-off-by: Julien Floret <julien.floret@6wind.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>