ArmVirtPkg/HighMemDxe: move to FDT client protocol

Use the FDT client protocol rather than parsing the DT directly using
fdtlib. While we're at it, update the code so it deals correctly with
memory nodes that describe multiple disjoint regions in their "reg"
properties, and make the code work with #address-cells/#size-cells
properties of <1> as well as <2>.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>

ArmVirtPkg/HighMemDxe/HighMemDxe.inf

@@ -1,7 +1,7 @@
 ## @file
 #  High memory node enumeration DXE driver for ARM Virtual Machines
 #
-#  Copyright (c) 2015, Linaro Ltd. All rights reserved.
+#  Copyright (c) 2015-2016, Linaro Ltd. All rights reserved.
 #
 #  This program and the accompanying materials are licensed and made available
 #  under the terms and conditions of the BSD License which accompanies this
@@ -30,23 +30,21 @@
   MdePkg/MdePkg.dec
   MdeModulePkg/MdeModulePkg.dec
   ArmPkg/ArmPkg.dec
-  ArmPlatformPkg/ArmPlatformPkg.dec
   ArmVirtPkg/ArmVirtPkg.dec
-  EmbeddedPkg/EmbeddedPkg.dec
 
 [LibraryClasses]
   BaseLib
-  PcdLib
-  UefiDriverEntryPoint
-  FdtLib
-  HobLib
+  DebugLib
   DxeServicesTableLib
+  PcdLib
+  UefiBootServicesTableLib
+  UefiDriverEntryPoint
 
-[Guids]
-  gFdtHobGuid
+[Protocols]
+  gFdtClientProtocolGuid                  ## CONSUMES
 
 [Pcd]
   gArmTokenSpaceGuid.PcdSystemMemoryBase
 
 [Depex]
-  gEfiCpuArchProtocolGuid
+  gEfiCpuArchProtocolGuid AND gFdtClientProtocolGuid