[Portenta] Add Cmake rules

Completes #13915

Author: facchinm

targets/TARGET_STM/TARGET_STM32H7/TARGET_STM32H747xI/TARGET_PORTENTA_H7/CMakeLists.txt

@@ -0,0 +1,15 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+target_sources(mbed-core
+    INTERFACE
+        PeripheralPins.c
+        system_clock_override.c
+        portenta_power.cpp
+)
+
+target_include_directories(mbed-core
+    INTERFACE
+        .
+)
+

targets/TARGET_STM/TARGET_STM32H7/TARGET_STM32H747xI/TARGET_PORTENTA_H7_M4/CMakeLists.txt

@@ -0,0 +1,18 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+set(STARTUP_FILE TOOLCHAIN_GCC_ARM/startup_stm32h747xx.S)
+set(LINKER_FILE TOOLCHAIN_GCC_ARM/STM32H747xI.ld)
+
+set_property(GLOBAL PROPERTY MBED_TARGET_LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/${LINKER_FILE})
+
+target_sources(mbed-core
+    INTERFACE
+        ${STARTUP_FILE}
+)
+
+target_include_directories(mbed-core
+    INTERFACE
+        .
+)
+

targets/TARGET_STM/TARGET_STM32H7/TARGET_STM32H747xI/TARGET_PORTENTA_H7_M7/CMakeLists.txt

@@ -0,0 +1,18 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+set(STARTUP_FILE TOOLCHAIN_GCC_ARM/startup_stm32h747xx.S)
+set(LINKER_FILE TOOLCHAIN_GCC_ARM/STM32H747xI.ld)
+
+set_property(GLOBAL PROPERTY MBED_TARGET_LINKER_FILE ${CMAKE_CURRENT_SOURCE_DIR}/${LINKER_FILE})
+
+target_sources(mbed-core
+    INTERFACE
+        ${STARTUP_FILE}
+)
+
+target_include_directories(mbed-core
+    INTERFACE
+        .
+)
+