qcam: Support Qt versions earlier than 5.9

The QtEventDispatcher timers implementation depends on Qt 5.9 or newer
due to the use of QObject::startTimer(std::chrono::milliseconds).
Support earlier Qt versions by using the QObject::startTimer(int)
version instead.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
1 file changed