C2SoftHEVCEnc: Add support for constant quality encoding

Quality (0 to 100) is used to map to Qp
Complexity (0 to 10) is used to map to presets

Test: Manual using an AMediaCodec based application
Bug: 125010575

Change-Id: Ia664c15bc1521b9f6183cb873705134ddb0692d8
3 files changed