BUG/MINOR: quic: set IP_PKTINFO socket option for QUIC receivers only

BUG/MINOR: quic: set IP_PKTINFO socket option for QUIC receivers only

Move code which activates IP_PKTINFO socket option (or affiliated
options) from sock_inet_bind_receiver() to quic_bind_listener()
function. This change is useful for two reasons :

* first, and the most important one : this activates IP_PKTINFO only for
  QUIC receivers. The previous version impacted all datagram receivers,
  used for example by log-forwarder. This should reduce memory usage for
  these datagram sockets which do not need this option.

* second, USE_QUIC preprocessor statements are removed from
  src/sock_inet.c which clean up the code.

IP_PKTINFO was introduced recently by the following patch :
  97ecc7a8ea5339a753507c3d4e4cd83028c6d038 (quic-dev/qns)
  MEDIUM: quic: retrieve frontend destination address

For the moment, this does not impact any stable release. However, as
previous patch is scheduled for 2.6 backporting, the current change must
also be backported to the same versions.