Add FREEZE_TIMER_ON_DEBUG condition

In order to give the choice to enable or not the timer freeze on stop/breakpoint.
This has to be defined in the mbed_app.json file for example.

Author: bcostm

targets/TARGET_STM/hal_tick_16b.c

@@ -148,12 +148,11 @@ HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority)
     // Enable timer
     HAL_TIM_Base_Start(&TimMasterHandle);
 
-#ifndef NDEBUG
-#ifdef TIM_MST_DBGMCU_FREEZE
     // Freeze timer on stop/breakpoint
+    // Define the FREEZE_TIMER_ON_DEBUG macro in mbed_app.json for example
+#if !defined(NDEBUG) && defined(FREEZE_TIMER_ON_DEBUG) && defined(TIM_MST_DBGMCU_FREEZE)
     TIM_MST_DBGMCU_FREEZE;
 #endif
-#endif
 
 #if DEBUG_TICK > 0
     __HAL_RCC_GPIOB_CLK_ENABLE();

targets/TARGET_STM/hal_tick_32b.c

@@ -118,12 +118,11 @@ HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority)
     __HAL_TIM_SET_COMPARE(&TimMasterHandle, TIM_CHANNEL_2, PreviousVal + HAL_TICK_DELAY);
     __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC2);
 
-#ifndef NDEBUG
-#ifdef TIM_MST_DBGMCU_FREEZE
     // Freeze timer on stop/breakpoint
+    // Define the FREEZE_TIMER_ON_DEBUG macro in mbed_app.json for example
+#if !defined(NDEBUG) && defined(FREEZE_TIMER_ON_DEBUG) && defined(TIM_MST_DBGMCU_FREEZE)
     TIM_MST_DBGMCU_FREEZE;
 #endif
-#endif
 
 #if DEBUG_TICK > 0
     __HAL_RCC_GPIOB_CLK_ENABLE();