_uart_isr use wr_addr != rd_addr as test for internal queue not empty (espressif#1849)

Author: qt1

cores/esp32/esp32-hal-uart.c

@@ -80,7 +80,7 @@ static void IRAM_ATTR _uart_isr(void *arg)
 uart->dev->int_clr.rxfifo_full=1;
 uart->dev->int_clr.frm_err=1;
 uart->dev->int_clr.rxfifo_tout=1;
-while(uart->dev->status.rxfifo_cnt){
+while(uart->dev->status.rxfifo_cnt|| (uart->dev->mem_rx_status.wr_addr!=uart->dev->mem_rx_status.rd_addr)){
 c=uart->dev->fifo.rw_byte;
 if(uart->queue!=NULL&& !xQueueIsQueueFullFromISR(uart->queue)){
 xQueueSendFromISR(uart->queue, &c, &xHigherPriorityTaskWoken);