Support building different variants of QtConnectivity library.
Support building different variants of QtConnectivity library.

 - Symbian^3 PS2 build has NFC and Bluetooth support.
 - Symbian^3 PS1 build has Bluetooth support only, NFC is a stub.
 - S60 5.0 build has Bluetooth support only, NFC is a stub.
 - S60 3.1 and 3.2 build only produces a stub library.

Note that installing Qt Mobility on a Symbian^3 PS1 device then
upgrading device firmware to PS2 will leave Qt Mobility NFC support
disabled until Qt Moboility is reinstalled/upgraded.

Task-number: MOBILITY-2482

qtproject/qt-mobility,KDE/android-qt-mobility,qtproject/qt-mobility,tmcguire/qt-mobility,tmcguire/qt-mobility,qtproject/qt-mobility,kaltsi/qt-mobility,tmcguire/qt-mobility,kaltsi/qt-mobility,kaltsi/qt-mobility,qtproject/qt-mobility,enthought/qt-mobility,KDE/android-qt-mobility,tmcguire/qt-mobility,enthought/qt-mobility,qtproject/qt-mobility,kaltsi/qt-mobility,KDE/android-qt-mobility,kaltsi/qt-mobility,enthought/qt-mobility,qtproject/qt-mobility,enthought/qt-mobility,enthought/qt-mobility,kaltsi/qt-mobility,KDE/android-qt-mobility,enthought/qt-mobility,tmcguire/qt-mobility