Strip tabs and trailing white spaces, and fix end of files (#748)

* format: Strip trailing whitespaces

We want to get rid of trailing whitespaces completly as they make just git
noice. Much better to start using automated tools to get rid of them once and
not getting them back again. This way git history will be cleaner and review
easier.

Commit was generated with:

    pre-commit run --all-files trailing-whitespace

* format: Files should have exactly one new line end of them

It is good practice that every file has one new line. It is not now days so
mandatory but it also is not nice if file has lot of newlines end of it. We will
use pre-commit which takes automatically care about this so let's fix all.

Commit was generated with:

    pre-commit run --all-files end-of-file-fixer

* format: Convert tabs to spaces

Project mostly use spaces over tabs. When mixing tabs and spaces this usually
makes formatting issues and also when changing those in commits it will make lot
of git noise. We will force spaces most of the time and use pre-commit to fix.

Commit was generated with:

    pre-commit run --all-files remove-tabs

---------

Co-authored-by: Kari Argillander <kari.argillander@fidelix.com>

apps/router-ipv6/main.c

@@ -565,7 +565,7 @@ static void send_who_is_router_to_network(uint16_t snet, uint16_t dnet)
  * @param src  [in] The routing source information, if any.
  *  If src->net and src->len are 0, there is no routing source information.
  * @param npdu_data [in] Contains a filled-out structure with information
- * 	decoded from the NCPI and other NPDU bytes.
+ *  decoded from the NCPI and other NPDU bytes.
  * @param npdu [in]  Buffer containing the rest of the NPDU, following the
  *  bytes that have already been decoded.
  * @param npdu_len [in] The length of the remaining NPDU message in npdu[].
@@ -618,7 +618,7 @@ static void who_is_router_to_network_handler(uint16_t snet,
  * @param src  [in] The routing source information, if any.
  *  If src->net and src->len are 0, there is no routing source information.
  * @param npdu_data [in] Contains a filled-out structure with information
- * 	decoded from the NCPI and other NPDU bytes.
+ *  decoded from the NCPI and other NPDU bytes.
  * @param npdu [in]  Buffer containing the rest of the NPDU, following the
  *  bytes that have already been decoded.
  * @param npdu_len [in] The length of the remaining NPDU message in npdu[].
@@ -899,7 +899,7 @@ static void routed_apdu_handler(uint16_t snet,
         while (port != NULL) {
             if (port->net != snet) {
                 datalink_send_pdu(port->net, dest, npdu, &Tx_Buffer[0],
-                	npdu_len + apdu_len);
+                    npdu_len + apdu_len);
             }
             port = port->next;
         }
@@ -979,7 +979,7 @@ static void my_routing_npdu_handler(
         }
     } else {
         fprintf(
-            stderr, "NPDU: unsupported protocol version %u.  Discarded!\n", 
+            stderr, "NPDU: unsupported protocol version %u.  Discarded!\n",
                 protocol_version);
     }
 
@@ -1118,7 +1118,7 @@ static void control_c_hooks(void)
  * @note This is a proxy function to satisfy the BACnet Stack IPv6 port layer
  * requirements since this application omits a Device object.
  */
-uint32_t Device_Object_Instance_Number(void) 
+uint32_t Device_Object_Instance_Number(void)
 {
     return Device_Instance_Number;
 }