features should be installed into QT_INSTALL_ARCHDATA

The QT_INSTALL_ARCHDATA path may be distro specific
on Manjaro it points to /usr/lib/qt5/mkspec/features
on SailfishOS it points to /usr/share/qt5/mkspec/features

root.pro

@@ -2,7 +2,7 @@ TEMPLATE = subdirs
 
 SUBDIRS = src tests type-to-cxx
 
-prf.path =  $$[QT_INSTALL_DATA]/mkspecs/features
+prf.path = $$[QT_INSTALL_ARCHDATA]/mkspecs/features
 prf.files = iodata-qt5.prf
 
 INSTALLS = prf