[C++] Update the comment for commandlines' size limit
[C++] Update the comment for commandlines' size limit

dalinaum/kati,google/kati,dalinaum/kati,danw/kati,pombredanne/kati,pombredanne/kati,shinh/kati,google/kati,colincross/kati,danw/kati,google/kati,dalinaum/kati,shinh/kati,colincross/kati,shinh/kati,colincross/kati,pombredanne/kati,colincross/kati,colincross/kati,dalinaum/kati,google/kati,pombredanne/kati,shinh/kati,danw/kati,shinh/kati,danw/kati,pombredanne/kati,danw/kati,shinh/kati,colincross/kati,danw/kati,dalinaum/kati,google/kati,pombredanne/kati