restore add_cfunc and add_cxxfunc for project
restore add_cfunc and add_cxxfunc for project

tboox/xmake,waruqi/xmake,tboox/xmake,waruqi/xmake,waruqi/xmake,waruqi/xmake,tboox/xmake,tboox/xmake,tboox/xmake,tboox/xmake,waruqi/xmake,waruqi/xmake,tboox/xmake,waruqi/xmake