Add functions to enable/disable debug logging (#280)

* Add "bip_debug_disable()"

* Add "bvlc_debug_disable()"

* Add setters for BIP_DL_Debug (BBMD registration debug logging)

ports/linux/bip-init.c

@@ -113,6 +113,14 @@ void bip_debug_enable(void)
     BIP_Debug = true;
 }
 
+/**
+ * @brief Disalbe debug printing of BACnet/IPv4
+ */
+void bip_debug_disable(void)
+{
+    BIP_Debug = false;
+}
+
 /**
  * @brief Set the BACnet IPv4 UDP port number
  * @param port - IPv4 UDP port number - in host byte order