Add QAndroidActivityResultReceiver to the documentation.

QAndroidActivityResultReceiver was missing the \inmodule command and
was therefore not shown in the class list.

Change-Id: Ide0670e7ff377420e9690b6ff5421bf5fe0d96e3
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>