stm32: microsecond timer: set correct period value (#4567)

Driver sets (period - 1) to ARR (auto-reload register)
So we need to set period to (1 << 32) to get maximum
0xffffffff value in ARR. But period is uint32_t.
So set it to 0 and it will ovelap to UINT32_MAX at
pwmp->tim->ARR  = pwmp->period - 1;

firmware/hw_layer/ports/stm32/microsecond_timer_stm32.cpp

@@ -33,17 +33,24 @@ static void hwTimerCallback(PWMDriver*) {
 }
 
 static constexpr PWMConfig timerConfig = {
-	SCHEDULER_TIMER_FREQ,
+	.frequency = SCHEDULER_TIMER_FREQ,
-	UINT32_MAX,		// timer period = 2^32 counts
+	/* wanted timer period = 2^32 counts,
-	nullptr,		// No update callback
+	 * but driver set (period - 1) value to register
-	{
+	 * also period is uint32_t
+	 * So set it to zero so it will overlap to 0xffffffff when writen to register */
+	.period = 0,
+	.callback = nullptr,		// No update callback
+	.channels = {
 		{PWM_OUTPUT_DISABLED, hwTimerCallback},	// Channel 0 = timer callback, others unused
 		{PWM_OUTPUT_DISABLED, nullptr},
 		{PWM_OUTPUT_DISABLED, nullptr},
 		{PWM_OUTPUT_DISABLED, nullptr}
 	},
-	0,	// CR1
+	.cr2 = 0,
-	0	// CR2
+#if STM32_PWM_USE_ADVANCED
+	.bdtr = 0,
+#endif
+	.dier = 0
 };
 
 void portInitMicrosecondTimer() {