Bugfix/bsd compile warnings (#307)

* Fix FreeBSD compile warnings

* remove example app from ports/bsd. OS based apps are in apps folder

Co-authored-by: Steve Karg <skarg@users.sourceforge.net>

src/bacnet/basic/service/h_ccov.c

@@ -189,7 +189,7 @@ CCOV_ABORT:
     if (bytes_sent <= 0) {
         PRINTF("CCOV: Failed to send PDU (%s)!\n", strerror(errno));
     }
-    bytes_sent = bytes_sent;
+    (void)bytes_sent;
 
     return;
 }