Added Test cases for DCB and EVB TLVs.
Added support for DCB and EVB TLVs

Added the support for ETS Configuration TLV, ETS Recommendation TLV, PFC Configuration TLV, Application Priority TLV, EVB TLV and CDCP TLV.
Test pcap files for DCB and EVB TLVs with their output
Merge pull request #331 from audaya/master

Support for DCB and EVB TLVs
Make some routines used outside print-lldp.c static.