ArmPlatformPkg: remove ArmTrustedMonitorLib definition and implementation

Remove ArmTrustedMonitorLib and its only [NULL] implementation.

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/ArmTrustedMonitorLib.h

@@ -1,24 +0,0 @@
-/** @file
-*  Main file supporting the Monitor World on ARM PLatforms
-*
-*  Copyright (c) 2011, ARM 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.
-*
-**/
-
-#ifndef __ARM_TRUSTED_MONITOR_LIB_H_
-#define __ARM_TRUSTED_MONITOR_LIB_H_
-
-VOID
-ArmSecureMonitorWorldInitialize (
-  VOID
-  );
-
-#endif