[libvirt] [PATCH 0/4] A bit of configure clear-up

Since on the whole it seems like the configure could see some cleanup, as it seem to use lots of older constructs and repeated code, I tried doing some basic cleaning. My changes also require autoconf-2.63… it could be something older as well, but 2.63 is new enough I'd say. If nobody has reasons for 2.59 compatibility to stick around, it would probably improve a lot. HTH! -- Diego