gluon

There are some devices not acting properly to roaming events, in that
they do not timely reissue IGMP/MLD reports after reconnecting.

To compensate for that this commit reduces the query interval from 125
seconds to 20 and the query response interval from 20 seconds to 5.
This reduces a timeout to 20+5 seconds in the worst-case (12.5s average)
after a roaming event for such broken devices. This should be below the
30s "impatient user threshold" and below any connection timeout.

Until the bridge multicast snooping + querier gets re-enabled this is a
no-op.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>