clua: add an interface "clua_dofile".

N/A

clua_dofile: load and pcall a lua source file.
note: when users call clua_dofunc before need to call clua_dofile.
example:
1. lua_State* state = luaL_newstate();
2. clua_dofile(state, filename);
3. clua_dofunc(state, funcname, "[d|i|s]>[d|i|s]", ...);

Signed-off-by: liminghao <liminghao@xiaomi.com>