PcAtChipsetPkg: Add PeiAcpiTimerLib to save Frequency in HOB

In V2:
1) Update PeiAcpiTimerLib base name to PeiAcpiTimerLib
2) Update PeiAcpiTimerLib to add the missing constructor to enable ACPI IO space
3) Update DxeAcpiTimerLib to cache frequency in constructor.

PeiAcpiTimerLib caches PerformanceCounterFrequency in HOB, then Pei and Dxe
AcpiTimerLib can share the same PerformanceCounterFrequency.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>

PcAtChipsetPkg/Library/AcpiTimerLib/PeiAcpiTimerLib.inf

@@ -0,0 +1,56 @@
+## @file
+#  PEI ACPI Timer Library
+#
+#  Provides basic timer support using the ACPI timer hardware.  The performance
+#  counter features are provided by the processors time stamp counter.
+#
+#  Note: The implementation uses the lower 24-bits of the ACPI timer and
+#  is compatible with both 24-bit and 32-bit ACPI timers.
+#
+#  Copyright (c) 2013 - 2018, Intel Corporation. All rights reserved.<BR>
+#  This program and the accompanying materials
+#  are licensed and made available under the terms and conditions of the BSD License
+#  which accompanies this distribution.  The full text of the license may be found at
+#  http://opensource.org/licenses/bsd-license.php
+#
+#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = PeiAcpiTimerLib
+  FILE_GUID                      = 3FCA54F6-E1A2-4B20-BE76-926B4B48BFAA
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = TimerLib|PEI_CORE PEIM
+  CONSTRUCTOR                    = AcpiTimerLibConstructor
+  MODULE_UNI_FILE                = PeiAcpiTimerLib.uni
+
+[Sources]
+  AcpiTimerLib.c
+  PeiAcpiTimerLib.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  PcAtChipsetPkg/PcAtChipsetPkg.dec
+
+[LibraryClasses]
+  BaseLib
+  PcdLib
+  PciLib
+  IoLib
+  DebugLib
+  HobLib
+
+[Pcd]
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoPciBusNumber             ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoPciDeviceNumber          ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoPciFunctionNumber        ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoPciEnableRegisterOffset  ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoBarEnableMask            ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoPciBarRegisterOffset     ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoPortBaseAddress          ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiPm1TmrOffset               ## CONSUMES
+  gPcAtChipsetPkgTokenSpaceGuid.PcdAcpiIoPortBaseAddressMask      ## CONSUMES