PcAtChipsetPkg/Rtc: Fix a UEFI Win7 boot hang issue

PcAtChipsetPkg/Rtc: Fix a UEFI Win7 boot hang issue

The patch updates the Century value in CMOS location specified
by FADT.Century to avoid UEFI Win7 hang during booting.
Per the ACPI spec if the FADT.Century is zero, it's not needed
to store the century value in CMOS. But UEFI Win7 treats the
Century storage is optional only when FADT.Century is 0x80.
While Linux strictly follows the ACPI spec and treats Century
storage is optional when FADT.Century is 0.
So if a platform wants to support both UEFI Win7 and Linux,
it needs to report FADT.Century to a traditional value which
doesn't equal to 0 or 0x80 (0x32 mostly). And RTC driver is
enhanced to save the century value to the location specified
by FADT.Century.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19442 6f19259b-4bc3-4df7-8a09-765794883524