Bugfix/code clean using gcc warnings (#371)

* Enable extra GCC warnings to discover subtle bugs

* convert c++ comments to c comments

* cleanup pedantic compiler warnings

* Compile apps with GNU89 GNU99 GNU11 and GNU17

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

src/bacnet/basic/object/netport.c

@@ -2561,6 +2561,8 @@ bool Network_Port_Write_Property(BACNET_WRITE_PROPERTY_DATA *wp_data)
  */
 int Network_Port_Read_Range_BDT(uint8_t *apdu, BACNET_READ_RANGE_DATA *pRequest)
 {
+    (void)apdu;
+    (void)pRequest;
     return 0;
 }
 
@@ -2574,6 +2576,8 @@ int Network_Port_Read_Range_BDT(uint8_t *apdu, BACNET_READ_RANGE_DATA *pRequest)
  */
 int Network_Port_Read_Range_FDT(uint8_t *apdu, BACNET_READ_RANGE_DATA *pRequest)
 {
+    (void)apdu;
+    (void)pRequest;
     return 0;
 }