Fix some batch file bugs.
Fix some batch file bugs.

Copy paste from unix configure and forgotten quoting when comparing
empty strings.

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