Hack to get posix build partially working

Created a dummy build_git_version.h so I did not have to figure out
how to generate it.

Commented out topic_listener.cpp from src/systemcmds/CMakeLists.txt
because it depends on a generated cpp file.

Link doesn't work mut many modules build

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

src/firmware/posix/CMakeLists.txt

@@ -1,3 +1,24 @@
-#TODO
+include(px4_base)
+
+set(module_dir_list)
+set(module_list)
+px4_posix_add_modules(module_dir_list ${BOARD})
+message(STATUS "module list: ${module_dir_list}")
+
+foreach(directory ${module_dir_list})
+	message(STATUS "directory: ${directory}")
+	px4_mangle_name(${directory} mangled_name)
+	list(APPEND module_list
+		${mangled_name})
+endforeach()
+px4_posix_generate_builtin_commands(
+	OUT builtin_commands.cpp
+	MODULE_LIST ${module_list})
+
+add_executable(mainapp builtin_commands.cpp)
+target_link_libraries(mainapp
+	${module_list}
+	pthread m
+	)
 
 # vim: set noet ft=cmake fenc=utf-8 ff=unix :