Merge pull request #706 from openziti/include.sys.time

ensure struct timeval is defined

includes/ziti/model_support.h

@@ -20,6 +20,7 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdlib.h>
+#include <sys/time.h>
 #endif
 
 #include <string.h>