Build: Update app_broker build

Update app_broker build to make dependencies more stable.

  - Sort NS library folder structure.
    Move common library folders out of app_broker. Place them under lib
    folder. Move CMSIS to lib/ext.
    It is expected that users can re-use those library in other NS
    integration with TF-M.
  - NS libraries depend on each other and therefore the dependencies are
    complicated. Build those NS libraries under app_broker to more
    easily sort out dependencies. Remove build files from library
    folders.

Signed-off-by: David Hu <david.hu@arm.com>
Change-Id: I8c2ff7bbec6c03738b9cbe49fd286a5147293ba5
diff --git a/tests_reg/CMakeLists.txt b/tests_reg/CMakeLists.txt
index ef95cca..a60f744 100644
--- a/tests_reg/CMakeLists.txt
+++ b/tests_reg/CMakeLists.txt
@@ -38,14 +38,13 @@
 # Test configurations
 include(${CMAKE_CURRENT_LIST_DIR}/test/config/default_test_config.cmake)
 
-add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../lib/ext ${CMAKE_BINARY_DIR}/lib/ext)
-
 include(${TFM_TOOLCHAIN_FILE})
 project(tfm_ns LANGUAGES C ASM)
 tfm_toolchain_reload_compiler()
 
 add_executable(tfm_ns)
 
+add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../lib/ext ${CMAKE_BINARY_DIR}/lib/ext)
 add_subdirectory(../app_broker ${CMAKE_BINARY_DIR}/app_broker)
 add_subdirectory(test)