ArmVirtPkg/ArmVirtQemu: add ArmVirtMemInfoLib implementation

Create a new ArmVirtMemInfoLib for ArmVirtQemuKernel by cloning the
existing ArmPlatformGetVirtualMemoryMap () for this platform,
(ArmQemuRelocatablePlatformLib *not* ArmVirtPlatformLib), and cleaning
it up:
- remove support for uncached DRAM mappings
- replace EFI_D_xxx with DEBUG_xxx throughout
- use a temp variable to hold the top of the physical address space
- use AllocatePool () instead of AllocatePages (), given that we use
  160 bytes only, and the memory is never freed.

In a future patch, we will add this library to the ordinary ArmVirtQemu
platform as well.

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

ArmVirtPkg/Library/QemuVirtMemInfoLib/Arm/PhysAddrTop.S

@@ -0,0 +1,24 @@
+#
+#  Copyright (c) 2011-2013, ARM Limited. All rights reserved.
+#  Copyright (c) 2014-2017, Linaro Limited. 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.
+#
+#
+
+#include <AsmMacroIoLib.h>
+
+//EFI_PHYSICAL_ADDRESS
+//GetPhysAddrTop (
+//  VOID
+//  );
+ASM_FUNC(ArmGetPhysAddrTop)
+  mov   r0, #0x00000000
+  mov   r1, #0x10000
+  bx    lr