npapi-headers: Disable do_compile

* to fix npapi-headers staging headers to HOME
* otherwise make is executed and headers staged in ${HOME}/ISIS_OUT/

Open-webOS-DCO-1.0-Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Change-Id: I99837494e7fd238359f5d146630c1230562538cd
Reviewed-on: http://g2g.palm.com/1140
Reviewed-by: Martin Jansa <martin.jansa@palm.com>
Tested-by: Martin Jansa <martin.jansa@palm.com>
Reviewed-by: Susan Montooth <susan.montooth@palm.com>