ShellPkg: Add AcpiViewCommandLib

The UefiShellAcpiViewCommandLib is converted from NULL library to a
named library so that it may be used in modules other than shell.
The library interface exposes the main method for to AcpiView
functionality as well as a helper method to dump a buffer to a file.

The Shell module is still built by pulling UefiShellAcpiViewCommandLib
as a NULL library to preserve the modularity of shell builds.

Cc: Ray Ni <ray.ni@intel.com>
Cc: Zhichao Gao <zhichao.gao@intel.com>
Reviewed-by: Zhichao Gao <zhichao.gao@intel.com>
Signed-off-by: Tomas Pilar <tomas.pilar@arm.com>

ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c

@@ -16,13 +16,13 @@
 #include <Library/ShellLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 #include <Library/UefiLib.h>
+#include <Library/AcpiViewCommandLib.h>
 #include <Uefi.h>
 
 #include "AcpiParser.h"
 #include "AcpiTableParser.h"
 #include "AcpiView.h"
 #include "AcpiViewConfig.h"
-#include "UefiShellAcpiViewCommandLib.h"
 
 CONST CHAR16 gShellAcpiViewFileName[] = L"ShellCommand";
 EFI_HII_HANDLE gShellAcpiViewHiiHandle = NULL;