Doesn't look like it. http://appcenter.html5tools-software.intel.com/TOS/

Seems fairly permissive, but has provisions to do with de-compiling anything distributed in binary form so it looks fairly mixed.

This may though just be due to use of some legacy, licensed library somewhere rather than deliberately restrictive licensing. I haven't looked closely at what comes with XDK so I'm not sure what components are used.