Include errno.h

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@2268 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_system.c

@@ -21,6 +21,7 @@
 #include <unistd.h>
 #include <string.h>
 #include <stdlib.h>
+#include <errno.h>
 
 #include <pthread.h>