Add lp/us ticker_free() functions stub.

This patch adds only empty stubs of `us_ticker_free()` and `lp_ticker_free()` for all boards where these functions are not implemented.

Author: mprse

targets/TARGET_ARM_SSG/TARGET_BEETLE/lp_ticker.c

@@ -152,4 +152,9 @@ void lp_ticker_clear_interrupt(void)
     DualTimer_ClearInterrupt(DUALTIMER0);
 }
 
+void lp_ticker_free(void)
+{
+
+}
+
 #endif

targets/TARGET_ARM_SSG/TARGET_BEETLE/us_ticker.c

@@ -111,3 +111,8 @@ void us_ticker_disable_interrupt(void) {
 void us_ticker_clear_interrupt(void) {
     Timer_ClearInterrupt(TIMER0);
 }
+
+void us_ticker_free(void)
+{
+
+}

targets/TARGET_ARM_SSG/TARGET_CM3DS_MPS2/lp_ticker.c

@@ -108,6 +108,11 @@ void lp_ticker_fire_interrupt(void)
     cmsdk_ticker_fire_interrupt(&timer_data);
 }
 
+void lp_ticker_free(void)
+{
+
+}
+
 void TIMER1_IRQHandler(void)
 {
     cmsdk_ticker_irq_handler(&timer_data);

targets/TARGET_ARM_SSG/TARGET_CM3DS_MPS2/us_ticker.c

@@ -112,6 +112,11 @@ void us_ticker_fire_interrupt(void)
     cmsdk_ticker_fire_interrupt(&timer_data);
 }
 
+void us_ticker_free(void)
+{
+
+}
+
 void TIMER0_IRQHandler(void)
 {
     cmsdk_ticker_irq_handler(&timer_data);

targets/TARGET_ARM_SSG/TARGET_IOTSS/us_ticker.c

@@ -87,3 +87,8 @@ void us_ticker_clear_interrupt(void) {
     US_TICKER_TIMER2->TimerIntClr = 0x1;
 
 }
+
+void us_ticker_free(void)
+{
+
+}

targets/TARGET_ARM_SSG/TARGET_MPS2/us_ticker.c

@@ -81,3 +81,8 @@ void us_ticker_clear_interrupt(void) {
     US_TICKER_TIMER2->TimerIntClr = 0x1;
 
 }
+
+void us_ticker_free(void)
+{
+
+}

targets/TARGET_Analog_Devices/TARGET_ADUCM302X/TARGET_ADUCM3029/api/us_ticker.c

@@ -355,6 +355,10 @@ void us_ticker_fire_interrupt(void)
     event_timer();                             // enable the timer and interrupt
 }
 
+void us_ticker_free(void)
+{
+
+}
 
 /*
 ** EOF

targets/TARGET_Analog_Devices/TARGET_ADUCM4X50/TARGET_ADUCM4050/api/us_ticker.c

@@ -353,6 +353,10 @@ void us_ticker_fire_interrupt(void)
     event_timer();                             // enable the timer and interrupt
 }
 
+void us_ticker_free(void)
+{
+
+}
 
 /*
 ** EOF

targets/TARGET_Atmel/TARGET_SAM_CortexM0P/us_ticker.c

@@ -167,3 +167,8 @@ void us_ticker_clear_interrupt(void)
     tc_clear_interrupt(&us_ticker_module, TC_CALLBACK_CC_CHANNEL0);
     NVIC_ClearPendingIRQ(TICKER_COUNTER_IRQn);
 }
+
+void us_ticker_free(void)
+{
+
+}

targets/TARGET_Atmel/TARGET_SAM_CortexM4/lp_ticker.c

@@ -131,3 +131,8 @@ void lp_ticker_clear_interrupt(void)
 {
     NVIC_ClearPendingIRQ(TICKER_COUNTER_IRQn2);
 }
+
+void lp_ticker_free(void)
+{
+
+}