Allow to redefine Exception handler

By default, all Interruption and Exception Handlers are weaked and
aliased to Default_Handler (Infinite Loop, See CMSIS device startup file)
So, those defined handlers in the core doing a loop bring nothing
except to not allow further redefinition.
But this is what we want, be able to redefine those handler.
Ex: FreeRTOS library requires to be able to redefine them.

Signed-off-by: Frederic.Pillon <frederic.pillon@st.com>

Author: fpistm

cores/arduino/stm32/hw_config.c

@@ -114,110 +114,6 @@ void hw_config_init(void)
   SystemClock_Config();
 }
 
-/******************************************************************************/
-/*            Cortex-M4 Processor Interruption and Exception Handlers         */
-/******************************************************************************/
-
-/**
-* @brief This function handles Non maskable interrupt.
-*/
-void NMI_Handler(void)
-{
-  /* USER CODE BEGIN NonMaskableInt_IRQn 0 */
-
-  /* USER CODE END NonMaskableInt_IRQn 0 */
-
-  /* USER CODE BEGIN NonMaskableInt_IRQn 1 */
-
-  /* USER CODE END NonMaskableInt_IRQn 1 */
-
-}
-
-/**
-* @brief This function handles Hard fault interrupt.
-*/
-void HardFault_Handler(void)
-{
-  /* USER CODE BEGIN HardFault_IRQn 0 */
-
-  /* USER CODE END HardFault_IRQn 0 */
-  while (1)
-  {
-  }
-  /* USER CODE BEGIN HardFault_IRQn 1 */
-
-  /* USER CODE END HardFault_IRQn 1 */
-}
-
-/**
-* @brief This function handles Memory management fault.
-*/
-void MemManage_Handler(void)
-{
-
-  /* USER CODE BEGIN MemoryManagement_IRQn 0 */
-
-  /* USER CODE END MemoryManagement_IRQn 0 */
-  while (1)
-  {
-  }
-  /* USER CODE BEGIN MemoryManagement_IRQn 1 */
-
-  /* USER CODE END MemoryManagement_IRQn 1 */
-}
-
-/**
-* @brief This function handles Pre-fetch fault, memory access fault.
-*/
-void BusFault_Handler(void)
-{
-
-  /* USER CODE BEGIN BusFault_IRQn 0 */
-
-  /* USER CODE END BusFault_IRQn 0 */
-  while (1)
-  {
-  }
-  /* USER CODE BEGIN BusFault_IRQn 1 */
-
-  /* USER CODE END BusFault_IRQn 1 */
-}
-
-/**
-* @brief This function handles Undefined instruction or illegal state.
-*/
-void UsageFault_Handler(void)
-{
-
-  /* USER CODE BEGIN UsageFault_IRQn 0 */
-
-  /* USER CODE END UsageFault_IRQn 0 */
-  while (1)
-  {
-  }
-  /* USER CODE BEGIN UsageFault_IRQn 1 */
-
-  /* USER CODE END UsageFault_IRQn 1 */
-}
-
-/**
-* @brief This function handles Debug monitor.
-*/
-void DebugMon_Handler(void)
-{
-
-  /* USER CODE BEGIN DebugMonitor_IRQn 0 */
-
-  /* USER CODE END DebugMonitor_IRQn 0 */
-  while (1)
-  {
-  }
-  /* USER CODE BEGIN DebugMonitor_IRQn 1 */
-
-  /* USER CODE END DebugMonitor_IRQn 1 */
-}
-
-
 /**
   * @}
   */