OvmfPkg/OvmfXen: use RealTimeClockRuntimeDxe from EmbeddedPkg

A Xen PVH guest doesn't have a RTC that OVMF would expect, so
PcatRealTimeClockRuntimeDxe fails to initialize and prevent the
firmware from finish to boot. To prevent that, we will use
XenRealTimeClockLib which simply always return the same time.
This will work on both Xen PVH and HVM guests.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1689
Signed-off-by: Anthony PERARD <[email protected]>
Acked-by: Laszlo Ersek <[email protected]>
Message-Id: <[email protected]>

OvmfPkg/OvmfXen.dsc

@@ -199,6 +199,7 @@
 
   Tcg2PhysicalPresenceLib|OvmfPkg/Library/Tcg2PhysicalPresenceLibNull/DxeTcg2PhysicalPresenceLib.inf
   TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf
+  RealTimeClockLib|OvmfPkg/Library/XenRealTimeClockLib/XenRealTimeClockLib.inf
 
 [LibraryClasses.common]
   BaseCryptLib|CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf
@@ -564,7 +565,7 @@
   }
   MdeModulePkg/Universal/ResetSystemRuntimeDxe/ResetSystemRuntimeDxe.inf
   MdeModulePkg/Universal/Metronome/Metronome.inf
-  PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcatRealTimeClockRuntimeDxe.inf
+  EmbeddedPkg/RealTimeClockRuntimeDxe/RealTimeClockRuntimeDxe.inf
   MdeModulePkg/Universal/DriverHealthManagerDxe/DriverHealthManagerDxe.inf
   MdeModulePkg/Universal/BdsDxe/BdsDxe.inf {
     <LibraryClasses>

OvmfPkg/OvmfXen.fdf

@@ -307,7 +307,7 @@ INF  MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf
 INF  MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf
 INF  MdeModulePkg/Universal/ResetSystemRuntimeDxe/ResetSystemRuntimeDxe.inf
 INF  MdeModulePkg/Universal/Metronome/Metronome.inf
-INF  PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcatRealTimeClockRuntimeDxe.inf
+INF  EmbeddedPkg/RealTimeClockRuntimeDxe/RealTimeClockRuntimeDxe.inf
 
 INF  OvmfPkg/XenIoPvhDxe/XenIoPvhDxe.inf
 INF  OvmfPkg/XenIoPciDxe/XenIoPciDxe.inf