Define FixedPCD's to replace macros in RTC driver, to allow for platform-specific configurations. Cc: Ruiyu Ni <ruiyu.ni@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Leo Duran <leo.duran@amd.com> Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>