Update to YAJL-2.0

:Release Notes:
Fix build with YAJL-2.0
Build with clang

:Detailed Notes:

:Testing Performed:
Build succeeded. All unit tests passed

:QA Notes:

:Issues Addressed:
[GF-8140] Upgrade libpbnjson to YAJL-2

Open-webOS-DCO-1.0-Signed-off-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>

Change-Id: I6f95cef8cf3cb47ad53aaf28d3372805e568ffa2
Reviewed-on: https://g2g.palm.com/3016
Reviewed-by: Build Verification
Tested-by: Mykola Kryvonos <mykola.kryvonos@lge.com>
Reviewed-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>
Tested-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>