Find Qt5 libraries for examples

This fixes issue introduced in 14511 resolution where dashboards were reporting
a build failure against Qt5:
Qt5::Widgets library not found while building libSMMyElevation.so

Change-Id: Ib963c6367fe57493b396cb3fa43cbf0e6860ce8d
Merge topic 'fix_example_qt5' into next

0e42721f Find Qt5 libraries for examples