ArmPlatformPkg: remove ArmPlatformInitializeSystemMemory

The function ArmPlatformInitializeSystemMemory() is defined by
ArmPlatformLib, but is only ever called when using the PrePeiCore
flavor of the startup code. Also, none of the remaining upstream
platforms actually implement anything in that function in the first
place. So let's just remove it altogether.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

ArmPlatformPkg/Include/Library/ArmPlatformLib.h

@@ -111,17 +111,6 @@ ArmPlatformInitialize (
   IN  UINTN                     MpId
   );
 
-/**
-  Initialize the system (or sometimes called permanent) memory
-
-  This memory is generally represented by the DRAM.
-
-**/
-VOID
-ArmPlatformInitializeSystemMemory (
-  VOID
-  );
-
 /**
   Return the Virtual Memory Map of your platform