gupnp-service-proxy: remove subscription timeout on subscribe
gupnp-service-proxy: remove subscription timeout on subscribe

We have seen crashes in subscription_expire() where user_data
pointed to invalid memory. I do not see an obvious way how this
can have happened, but it seems like a good idea to always
remove the subscription timeout when sending a new subscription
request.

Signed-off-by: Sven Neumann <de9c8eafc191771e2f399a547ee7c54d9a869f0b@teufel.de>

GNOME/gupnp,GNOME/gupnp,GNOME/gupnp,GNOME/gupnp