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>

ports/stm32f4xx/stm32f4xx_it.c

@@ -1,11 +1,11 @@
 /**
   ******************************************************************************
-  * @file    IO_Toggle/stm32f4xx_it.c 
+  * @file    IO_Toggle/stm32f4xx_it.c
   * @author  MCD Application Team
   * @version V1.0.0
   * @date    19-September-2011
   * @brief   Main Interrupt Service Routines.
-  *          This file provides template for all exceptions handler and 
+  *          This file provides template for all exceptions handler and
   *          peripherals interrupt service routine.
   ******************************************************************************
   * @attention
@@ -19,7 +19,7 @@
   *
   * <h2><center>&copy; COPYRIGHT 2011 STMicroelectronics</center></h2>
   ******************************************************************************
-  */ 
+  */
 
 /* Includes ------------------------------------------------------------------*/
 #include "stm32f4xx_it.h"
@@ -31,7 +31,7 @@
 
 /** @addtogroup IO_Toggle
   * @{
-  */ 
+  */
 
 /* Private typedef -----------------------------------------------------------*/
 /* Private define ------------------------------------------------------------*/
@@ -151,6 +151,6 @@ void PendSV_Handler(void)
 
 /**
   * @}
-  */ 
+  */
 
 /******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/