Currently, pupnp is using a blocking connect to sends GENA
notifications. As a result, when there is a lot of notifications with
CPs which were disconnected without unsusbcribing, all the pupnp
threads are blocked for 20s (timeout). To correct this issue, this
patch replace the call to connect with a call to private_connect and add
a compilation flag to disable blocking TCP connections, so if we are not
able to connect to the CP, the notification is lost.
(cherry picked from commit 32cffb5bb55a650b1eb962c6fe2e58e6bf4fe2c5)
8811bf7ede