GMPLS update - 41: optimizing out-segment statistics entries

Hard-linked #out-segment #statistics through #standard #out-segment #entries in GMPLS module. This will indicate the #out-segment #attributes like #bytes sent, #packets sent, #erroneous packets, #discarded packets,  etc ... This will reduce the memory requirement associated with the out-segment statistics. The hard-linked out-segment statistics entries enables accessing them directly from the standard out-segment instance entries.

#GMPLS update 41 ...
[commit 2010f5ac47fdba15ebe935468b3ecb20d0a51fda] (https://github.com/nes-repo/NES-Open-Switch/commit/2010f5ac47fdba15ebe935468b3ecb20d0a51fda)