squashed warning

mongoose.c

@@ -1231,7 +1231,8 @@ static struct dirent *readdir(DIR *dir) {
 static int poll(struct pollfd *pfd, int n, int milliseconds) {
   struct timeval tv;
   fd_set set;
-  int i, result, maxfd = 0;
+  int i, result;
+  SOCKET maxfd = 0;
 
   tv.tv_sec = milliseconds / 1000;
   tv.tv_usec = (milliseconds % 1000) * 1000;