add extra warning about using non-installed prefix build of qt
add extra warning about using non-installed prefix build of qt

Change-Id: I7c618bbac6227b372bfe966c04433a60c39932a0
Reviewed-by: Daniel Teske <d8a411aec9a206efedb4d45b75fe8d13f1e2b628@nokia.com>

Distrotech/qtcreator,danimo/qt-creator,amyvmiwei/qt-creator,darksylinc/qt-creator,syntheticpp/qt-creator,xianian/qt-creator,farseerri/git_code,martyone/sailfish-qtcreator,kuba1/qtcreator,malikcjm/qtcreator,malikcjm/qtcreator,malikcjm/qtcreator,colede/qtcreator,omniacreator/qtcreator,kuba1/qtcreator,xianian/qt-creator,omniacreator/qtcreator,farseerri/git_code,AltarBeastiful/qt-creator,richardmg/qtcreator,richardmg/qtcreator,farseerri/git_code,AltarBeastiful/qt-creator,duythanhphan/qt-creator,Distrotech/qtcreator,KDE/android-qt-creator,amyvmiwei/qt-creator,amyvmiwei/qt-creator,danimo/qt-creator,danimo/qt-creator,maui-packages/qt-creator,richardmg/qtcreator,martyone/sailfish-qtcreator,danimo/qt-creator,KDE/android-qt-creator,richardmg/qtcreator,xianian/qt-creator,darksylinc/qt-creator,omniacreator/qtcreator,martyone/sailfish-qtcreator,martyone/sailfish-qtcreator,xianian/qt-creator,duythanhphan/qt-creator,darksylinc/qt-creator,kuba1/qtcreator,syntheticpp/qt-creator,colede/qtcreator,syntheticpp/qt-creator,maui-packages/qt-creator,syntheticpp/qt-creator,duythanhphan/qt-creator,KDE/android-qt-creator,kuba1/qtcreator,malikcjm/qtcreator,amyvmiwei/qt-creator,amyvmiwei/qt-creator,danimo/qt-creator,danimo/qt-creator,AltarBeastiful/qt-creator,Distrotech/qtcreator,omniacreator/qtcreator,xianian/qt-creator,Distrotech/qtcreator,maui-packages/qt-creator,danimo/qt-creator,farseerri/git_code,kuba1/qtcreator,colede/qtcreator,duythanhphan/qt-creator,syntheticpp/qt-creator,syntheticpp/qt-creator,farseerri/git_code,KDE/android-qt-creator,colede/qtcreator,kuba1/qtcreator,kuba1/qtcreator,KDE/android-qt-creator,amyvmiwei/qt-creator,richardmg/qtcreator,malikcjm/qtcreator,xianian/qt-creator,amyvmiwei/qt-creator,KDE/android-qt-creator,darksylinc/qt-creator,malikcjm/qtcreator,darksylinc/qt-creator,farseerri/git_code,danimo/qt-creator,colede/qtcreator,duythanhphan/qt-creator,colede/qtcreator,darksylinc/qt-creator,kuba1/qtcreator,xianian/qt-creator,farseerri/git_code,KDE/android-qt-creator,martyone/sailfish-qtcreator,duythanhphan/qt-creator,AltarBeastiful/qt-creator,maui-packages/qt-creator,richardmg/qtcreator,omniacreator/qtcreator,maui-packages/qt-creator,AltarBeastiful/qt-creator,maui-packages/qt-creator,martyone/sailfish-qtcreator,Distrotech/qtcreator,KDE/android-qt-creator,xianian/qt-creator,amyvmiwei/qt-creator,malikcjm/qtcreator,kuba1/qtcreator,darksylinc/qt-creator,AltarBeastiful/qt-creator,xianian/qt-creator,Distrotech/qtcreator,martyone/sailfish-qtcreator,syntheticpp/qt-creator,farseerri/git_code,richardmg/qtcreator,colede/qtcreator,omniacreator/qtcreator,omniacreator/qtcreator,martyone/sailfish-qtcreator,duythanhphan/qt-creator,AltarBeastiful/qt-creator,maui-packages/qt-creator,AltarBeastiful/qt-creator,darksylinc/qt-creator,danimo/qt-creator,Distrotech/qtcreator,martyone/sailfish-qtcreator