CMake: Enable post binary hook for ARM_MUSCA_B1

Author: LDong-Arm

targets/TARGET_ARM_SSG/TARGET_MUSCA_B1/CMakeLists.txt

@@ -1,6 +1,8 @@
 # Copyright (c) 2020-2021 ARM Limited. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
+include(${MBED_PATH}/tools/psa/tfm/bin_utils/mbed_set_post_build_tfm.cmake)
+
 add_library(mbed-arm-musca-b1 INTERFACE)
 
 if(${MBED_TOOLCHAIN} STREQUAL "ARM")
@@ -52,3 +54,10 @@ target_link_libraries(mbed-arm-musca-b1
         ${CMAKE_CURRENT_SOURCE_DIR}/s_veneers.o
         mbed-arm-ssg
 )
+
+mbed_post_build_tfm_sign_image(
+    ARM_MUSCA_B1
+    musca_b1
+    ${CMAKE_CURRENT_SOURCE_DIR}
+    ${CMAKE_CURRENT_SOURCE_DIR}/tfm_s.bin
+)