[Udpcast] [PATCH] Mac OS X Fixes

This patch applies to 20070602 and has a few fixes needed for OS X 10.4.

* removes 3 harmless warnings in fifo.c, log.c, statistics.c, and util.c

* drops the fatal error when getting the broadcast address fails for an interface, since this is normal for the loopback, which is checked before the ethernet. This causes udpcast to always die unless the -- interface option is used.

* use the alternative IP_MULTICAST_IF method, same as for Cygwin. The comment in the code made it sound like Cygwin was out of the norm, but it's Linux that's at ends with OpenBSD, Apple OS X, Solaris, Cygwin, etc...

Thanks, Devin Bayer