Platform: Reorganize and rename sse_200_mps2 folder

This patch reorganizes and renames sse_200_mps2
folder to be able to add new MPS2 subsystems.
The patch applies the following changes:
- renames sse_200_mps2 to mps2 in order to be
  able to add new MPS2 subsystems
- create the an521 folder to add all SMM-SSE-200
  files. AN521 is the name of Soft Macro
  Model (SMM) SSE-200 subsytem for MPS2
- refactor smm_mps2.h file to make it generic
  across all mps2 subsystems.
- updates cmake files to use the new paths
- removes unnecessary include files in cmake
  setting files
- removes unnecessary files for mps2 and an521

Change-Id: I1ceb1e371fdfb90ac4aa1e3403868a3f01ada2e6
Signed-off-by: Marc Moreno <marc.morenoberengue@arm.com>
diff --git a/secure_fw/spm/CMakeLists.inc b/secure_fw/spm/CMakeLists.inc
index 015d635..e3f05f6 100644
--- a/secure_fw/spm/CMakeLists.inc
+++ b/secure_fw/spm/CMakeLists.inc
@@ -40,7 +40,21 @@
 embedded_include_directories(PATH ${TFM_ROOT_DIR}/secure_fw/core ABSOLUTE)
 embedded_include_directories(PATH ${TFM_ROOT_DIR} ABSOLUTE)
 
-set(PLATFORM_DIR ${TFM_ROOT_DIR}/platform/ext)
-embedded_include_directories(PATH "${PLATFORM_DIR}/cmsis" ABSOLUTE)
-embedded_include_directories(PATH "${PLATFORM_DIR}/target/sse_200_mps2/cmsis_core" ABSOLUTE)
-embedded_include_directories(PATH "${PLATFORM_DIR}/target/sse_200_mps2/sse_200/retarget" ABSOLUTE)
+set(BUILD_CMSIS_CORE Off)
+set(BUILD_RETARGET Off)
+set(BUILD_NATIVE_DRIVERS Off)
+set(BUILD_STARTUP Off)
+set(BUILD_TARGET_CFG Off)
+set(BUILD_TARGET_HARDWARE_KEYS Off)
+set(BUILD_CMSIS_DRIVERS Off)
+set(BUILD_TIME Off)
+set(BUILD_UART_STDOUT Off)
+set(BUILD_FLASH Off)
+if(NOT DEFINED PLATFORM_CMAKE_FILE)
+	message (FATAL_ERROR "Platform specific CMake is not defined. Please set PLATFORM_CMAKE_FILE.")
+elseif(NOT EXISTS ${PLATFORM_CMAKE_FILE})
+	message (FATAL_ERROR "Platform specific CMake \"${PLATFORM_CMAKE_FILE}\" file does not exist. Please fix value of PLATFORM_CMAKE_FILE.")
+else()
+	include(${PLATFORM_CMAKE_FILE})
+endif()
+