The changes done in this commit are to contribute the supporting changes
for the existing "Initial support for RedCap" feature in gNB.
In this patch, handle and store the RedCap related IE's present in "NR
UE Capability Information" msg which are
- 'supportOfRedCap-r17'
- 'supportOf16DRB-RedCap-r17'
- 'longSN-RedCap-r17'
- 'am-WithLongSN-RedCap-r17'
use 'longSN-RedCap-r17' and 'am-WithLongSN-RedCap-r17' IEs to set the SN
length to either 12 Bit or 18 Bit accordingly.