rexecd: fix compile warning

rexecd.c:196:9: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]

Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>

netutils/rexecd/rexecd.c

@@ -176,6 +176,7 @@ int main(int argc, FAR char **argv)
   memset(&addr, 0, sizeof(addr));
   switch (family)
     {
+      default:
       case AF_INET:
         ((FAR struct sockaddr_in *)&addr)->sin_family = AF_INET;
         ((FAR struct sockaddr_in *)&addr)->sin_port = REXECD_PORT;