[Libvir] [PATCH 4/8] Compile libvirt under Windows (Cygwin)

'getaddrinfo' isn't available under Cygwin. This patch adds a general feature detection for getaddrinfo and getnameinfo and if they are not present replaces them with equivalents which we ship. The replacements come from this BSD-licensed implementation by Motoyuki Kasahara: http://www.sra.co.jp/people/m-kasahr/getaddrinfo/ Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903