devel/upnp: Update to 1.12.1

• Fix bug about setsockopt(IP_MULTICAST_IF) on 64-bit CPUs.
• Stop using usleep when using newer POSIX C source as it is now deprecated.
• Add Os/UserAgent information to UpnpActionRequest and UpnpFileInfo.
• Add CtrlPtIPAddr to UpnpFileInfo class.
• List: Add extern C for C++ users.

Approved by: tcberner (co-mentor)
Differential Revision: https://reviews.freebsd.org/D24382