Android Settings Ui: Rename label for ant location

To clarify that it points to the executable not a directory

Task-number: QTCREATORBUG-10680
Change-Id: I78b13033e21425b8f1662b63316687c13c7755a0
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>