Let vkjson use jsoncpp lib

The original cjson lib won't be available after changes in LVL upstream
get merged. Thus need to replace cjson with jsoncpp lib in vkjson.

Test: adb shell cmd gpu vkjson
Bug: b/77613206
Change-Id: I7d47d684759ca0905cf0fd56a3b3029d56023cd3
2 files changed