OvmfPkg/AcpiPlatformDxe: Fix Visual Studio build issues

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13602 6f19259b-4bc3-4df7-8a09-765794883524
MU SOURCE COMMIT:26af9aca92e11b77dbb9cf942d9dae92a71bfbbd

Platforms/OvmfPkg/AcpiPlatformDxe/Qemu.c

@@ -268,8 +268,8 @@ QemuInstallAcpiSsdtTable (
         *(UINT32*) SsdtPtr = sizeof (*FwData);
         SsdtPtr += 4;
 
-        ASSERT(SsdtPtr - Ssdt == SsdtSize);
-        ((EFI_ACPI_DESCRIPTION_HEADER *) Ssdt)->Length = SsdtSize;
+        ASSERT((UINTN) (SsdtPtr - Ssdt) == SsdtSize);
+        ((EFI_ACPI_DESCRIPTION_HEADER *) Ssdt)->Length = (UINT32) SsdtSize;
         Status = InstallAcpiTable (AcpiProtocol, Ssdt, SsdtSize, TableKey);
       }
 

Platforms/OvmfPkg/AcpiPlatformDxe/Xen.c

@@ -188,7 +188,7 @@ InstallXenTables (
       CurrentTableEntry = (VOID *) ((UINT8 *) Xsdt +
                             sizeof (EFI_ACPI_DESCRIPTION_HEADER) +
                             Index * sizeof (UINT64));
-      CurrentTablePointer = *(UINT64 *)CurrentTableEntry;
+      CurrentTablePointer = (UINTN) *(UINT64 *)CurrentTableEntry;
       CurrentTable = (EFI_ACPI_DESCRIPTION_HEADER *) CurrentTablePointer;
 
       //