qtbase: create empty oe-device-extra.pri
qtbase: create empty oe-device-extra.pri

During configure, it complains it can't find oe-device-extra.pri,
but it doesn't result in any error. Fix it, though, just in case.

Signed-off-by: Herve Jourdain <a2a574f9705513524542f7fbeb45f80d5b3c0599@neuf.fr>
Signed-off-by: Martin Jansa <516df3ff67e1fa5d153800b15fb204c0a1a389dc@gmail.com>

timopulkkinen/meta-qt5,timopulkkinen/meta-qt5,opendreambox/meta-qt5,sapiippo/meta-qt5,meta-qt5/meta-qt5,schnitzeltony/meta-qt5,timopulkkinen/meta-qt5,opendreambox/meta-qt5,kraj/meta-qt5,kraj/meta-qt5,sapiippo/meta-qt5,opendreambox/meta-qt5,timopulkkinen/meta-qt5,schnitzeltony/meta-qt5,meta-qt5/meta-qt5