[Fix] <bsp>:gd32_uart_gpio_init 过早开中断触发断言rx_fifo == NULL

Solution: gd32_uart_gpio_init 不开中断
等驱动框架初始化好fifo后通过 device_control 开中断
Signed-off-by: Yucai Liu <1486344514@qq.com>

bsp/gd32/arm/libraries/gd32_drivers/drv_usart.c

@@ -416,7 +416,6 @@ void gd32_uart_gpio_init(struct gd32_uart *uart)
 #endif
 
     NVIC_SetPriority(uart->irqn, 0);
-    NVIC_EnableIRQ(uart->irqn);
 }
 
 /**