net-p2p/{lib,r}torrent: Update to 0.16.0

libtorrent:

• Remove gcc i386 build workaround as it builds fine
• Remove patch merged upstream

rtorrent:

• Remove XMLRPC option (and XML radio) Use only upstream recommended xmlrpc tinyxml2 wrapper
• Remove defunct IPV6 option
• Remove unneeded LDFLAGS

ChangeLog: https://github.com/rakshasa/rtorrent/releases/tag/v0.16.0

		https://github.com/rakshasa/rtorrent/releases/tag/v0.15.7