clean up HSE_VALUE for stm32

hw/bsp/stm32h743nucleo/stm32h743nucleo.c

@@ -94,7 +94,7 @@ static void SystemClock_Config(void)
   RCC_OscInitStruct.CSIState = RCC_CSI_OFF;
   RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
   RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
-  RCC_OscInitStruct.PLL.PLLM = 8;
+  RCC_OscInitStruct.PLL.PLLM = HSE_VALUE/1000000;
   RCC_OscInitStruct.PLL.PLLN = 336;
   RCC_OscInitStruct.PLL.PLLP = 2;
   RCC_OscInitStruct.PLL.PLLQ = 7;