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/ArmVirtQemuKernel.dsc

@@ -49,6 +49,7 @@
   QemuFwCfgS3Lib|OvmfPkg/Library/QemuFwCfgS3Lib/BaseQemuFwCfgS3LibNull.inf
 
   ArmPlatformLib|ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/ArmQemuRelocatablePlatformLib.inf
+  ArmVirtMemInfoLib|ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.inf
 
   TimerLib|ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.inf
   NorFlashPlatformLib|ArmVirtPkg/Library/NorFlashQemuLib/NorFlashQemuLib.inf