QemuOpenBoardPkg: Enable TimerLib for PEI Core in Stage2

During Stage2 the default TimerLib resolves to BaseTimerLibNullTemplate,
leading to a PeiCore ASSERT when timing services are invoked. Map
TimerLib to BaseAcpiTimerLib for PEI Core to provide a valid
implementation.

Signed-off-by: Vishal Oliyil Kunnil <[email protected]>

Author: vishalo

Platform/Qemu/QemuOpenBoardPkg/Include/Dsc/Stage2.dsc.inc

@@ -13,6 +13,9 @@
   PciHostBridgeUtilityLib | OvmfPkg/Library/PciHostBridgeUtilityLib/PciHostBridgeUtilityLib.inf
   DxeHardwareInfoLib      | OvmfPkg/Library/HardwareInfoLib/DxeHardwareInfoLib.inf
 
+[LibraryClasses.Common.PEI_CORE]
+  TimerLib                | OvmfPkg/Library/AcpiTimerLib/BaseAcpiTimerLib.inf
+
 [LibraryClasses.Common.PEIM]
   MpInitLib               | UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
   TimerLib                | OvmfPkg/Library/AcpiTimerLib/BaseAcpiTimerLib.inf