[XeTeX] how to use cid-x.map with xdvipdfmx

[luoyi]

hello, can I speicify a font  *should not*  be CID into the result pdf file ?

for example: my test.tex is as following:

luoyi at infos1:~/tex/Font/Type1$ cat test.tex
\font\lso="[DroidSerif-Regular.ttf]" \lso aaaaaaaaaaaaaaaaa \end


cid-x.map is as following:
luoyi at infos1:~/tex/Font/Type1$ cat cid-x.map
Droid at Unicode@ unicode !DroidSerif-Regular


but after xdvipdfmx , the ttf fonts still be embeded into the pdf file.