Fix misleading comment

Fix misleading comment: Disable instead of Enable
diff --git a/Src/stm32h7xx_hal_uart_ex.c b/Src/stm32h7xx_hal_uart_ex.c
index 6e5c0b2..bb45995 100644
--- a/Src/stm32h7xx_hal_uart_ex.c
+++ b/Src/stm32h7xx_hal_uart_ex.c
@@ -576,7 +576,7 @@
   /* Disable UART */
   __HAL_UART_DISABLE(huart);
 
-  /* Enable FIFO mode */
+  /* Disable FIFO mode */
   CLEAR_BIT(tmpcr1, USART_CR1_FIFOEN);
   huart->FifoMode = UART_FIFOMODE_DISABLE;