Update PCD PcdTcg2PhysicalPresenceFlags default setting. Also add PROMPT, HELP string. Cc: Star Zeng <star.zeng@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Chao Zhang <chao.b.zhang@intel.com> Reviewed-by: Star Zeng <star.zeng@intel.com>