Fix building on FreeBSD by including/not including some headers.

(closes issue #11218)
Reported by: ys
Patches:
      trunk89169.diff uploaded by ys (license 281)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@89177 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_unistim.c

@@ -41,6 +41,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include <unistd.h>
 #include <sys/socket.h>
 #include <sys/ioctl.h>
+#include <sys/stat.h>
 #include <net/if.h>
 #include <errno.h>
 #include <stdlib.h>