make sure iaxs gets initialized (bug #4856)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/v1-0@6252 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_iax2.c

@@ -7477,6 +7477,8 @@ int load_module(void)
 		ast_log(LOG_WARNING, "Unable to open IAX timing interface: %s\n", strerror(errno));
 #endif		
 
+	memset(iaxs, 0, sizeof(iaxs));
+
 	for (x=0;x<IAX_MAX_CALLS;x++)
 		ast_mutex_init(&iaxsl[x]);