ArmVirtPkg: introduce ArmVirtMemInfoLib library class

As part of the effort to get rid of ArmPlatformLib (which incorporates
far too many duties in a single library), introduce ArmVirtMemInfoLib
which will be invoked by our ArmVirtMemoryInitPeiLib implementation to
get a description of the virtual address space. This will allow us to
remove this functionality from ArmPlatformLib later, or, in the case of
ArmVirtXen and ArmVirtQemuKernel, drop ArmPlatformLib altogether.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>

ArmVirtPkg/Include/Library/ArmVirtMemInfoLib.h

@@ -0,0 +1,41 @@
+/** @file
+
+  Copyright (c) 2011-2013, ARM Limited. All rights reserved.
+  Copyright (c) 2017, 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
+  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.
+
+**/
+
+#ifndef _ARM_VIRT_MEMINFO_LIB_H_
+#define _ARM_VIRT_MEMINFO_LIB_H_
+
+#include <Base.h>
+#include <Library/ArmLib.h>
+
+/**
+  Return the Virtual Memory Map of your platform
+
+  This Virtual Memory Map is used by MemoryInitPei Module to initialize the MMU
+  on your platform.
+
+  @param[out]   VirtualMemoryMap    Array of ARM_MEMORY_REGION_DESCRIPTOR
+                                    describing a Physical-to-Virtual Memory
+                                    mapping. This array must be ended by a
+                                    zero-filled entry. The allocated memory
+                                    will not be freed.
+
+**/
+VOID
+EFIAPI
+ArmVirtGetMemoryMap (
+  OUT ARM_MEMORY_REGION_DESCRIPTOR    **VirtualMemoryMap
+  );
+
+#endif