Android: android.bat needs a special environment

See the below task for details:

Task-number: QTCREATORBUG-10575
Change-Id: I7756d8780b33ede4c3d4eac7e281c9eabfa47e35
Reviewed-by: Robert Loehning <robert.loehning@digia.com>
Reviewed-by: Daniel Teske <daniel.teske@digia.com>