native_sim: Add new native_sim board

Add the new native_sim board, based on the native simulator.

Signed-off-by: Alberto Escolar Piedras <alberto.escolar.piedras@nordicsemi.no>

CMakeLists.txt

@@ -1764,15 +1764,32 @@ if(CONFIG_BUILD_OUTPUT_STRIPPED)
 endif()
 
 if(CONFIG_BUILD_OUTPUT_EXE)
-  list(APPEND
-    post_build_commands
-    COMMAND
-    ${CMAKE_COMMAND} -E copy ${KERNEL_ELF_NAME} ${KERNEL_EXE_NAME}
-    )
-  list(APPEND
-    post_build_byproducts
-    ${KERNEL_EXE_NAME}
+  if (NOT CONFIG_NATIVE_LIBRARY)
+    list(APPEND
+      post_build_commands
+      COMMAND
+      ${CMAKE_COMMAND} -E copy ${KERNEL_ELF_NAME} ${KERNEL_EXE_NAME}
+      )
+    list(APPEND
+      post_build_byproducts
+      ${KERNEL_EXE_NAME}
+      )
+  else()
+    if(CMAKE_GENERATOR STREQUAL "Unix Makefiles")
+      set(MAKE "${CMAKE_MAKE_PROGRAM}" CACHE FILEPATH "cmake defined make")
+    endif()
+    find_program(MAKE make REQUIRED)
+    add_custom_target(native_runner_executable
+      ALL
+      COMMENT "Building native simulator runner, and linking final executable"
+      COMMAND
+      ${MAKE} -f ${ZEPHYR_BASE}/scripts/native_simulator/Makefile all --warn-undefined-variables
+        -r NSI_CONFIG_FILE=${CMAKE_BINARY_DIR}/zephyr/NSI/nsi_config
+      # nsi_config is created by the board cmake file
+      DEPENDS ${logical_target_for_zephyr_elf}
+      BYPRODUCTS ${KERNEL_EXE_NAME}
     )
+  endif()
 endif()
 
 if(CONFIG_BUILD_OUTPUT_INFO_HEADER)