tinydtls: provide implementation for sock_dtls_get_udp_sock
tinydtls: provide implementation for sock_dtls_get_udp_sock

ant9000/RIOT,basilfx/RIOT,authmillenon/RIOT,kaspar030/RIOT,OTAkeys/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,kaspar030/RIOT,kaspar030/RIOT,ant9000/RIOT,basilfx/RIOT,jasonatran/RIOT,jasonatran/RIOT,OTAkeys/RIOT,OTAkeys/RIOT,miri64/RIOT,ant9000/RIOT,kaspar030/RIOT,miri64/RIOT,basilfx/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,kYc0o/RIOT,OlegHahm/RIOT,miri64/RIOT,kYc0o/RIOT,miri64/RIOT,kYc0o/RIOT,kaspar030/RIOT,basilfx/RIOT,RIOT-OS/RIOT,miri64/RIOT,OlegHahm/RIOT,basilfx/RIOT,OTAkeys/RIOT,jasonatran/RIOT,ant9000/RIOT,authmillenon/RIOT,authmillenon/RIOT,OTAkeys/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,OlegHahm/RIOT,kYc0o/RIOT,jasonatran/RIOT,kYc0o/RIOT,authmillenon/RIOT,ant9000/RIOT