Use `std::forward()` to forward the received arguments to enable the
potential use of move constructors instead of copy constructors.
Commit 0eacde623b ("libcamera: object: Avoid argument copies in invokeMethod()")
added the forwarding references to `invokeMethod()` but it did not add the
appropriate `std::forward()` calls, so copying could still take place
even if not necessary.
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>