GMPLS update - 75: updating custom explicit-path agent mapper routines

Updated #custom #explicit-path agent mapper routines in GMPLS module. The agent #iterator routines and #mapper #routine has been updated to use standard #explicit-path entry based #indexing. This will access the explicit-path entries by using the #native #indexing. This removes references to the custom explicit-path indexing used earlier. This will reduce the memory requirement associated with the custom explicit-path entries. The custom explicit-path #entries add support for #attributes like #hop-forward-label and #hop-reverse-label. The #label-type attribute adds support for #media #specific labels ( #Ethernet / #SONET / #SDH / #OTN ) through the #label-type and #label-value attributes.

#GMPLS update 75 ...
[commit 9ec61638981ef073c8465a146aa2b84ebea969ad] (https://github.com/nes-repo/NES-Open-Switch/commit/9ec61638981ef073c8465a146aa2b84ebea969ad)