Update drv_can.c

删除多余注释，另外确定了对于其他型号单片机的适应性

bsp/stm32/libraries/HAL_Drivers/drv_can.c

@@ -336,10 +336,6 @@ static rt_err_t _can_control(struct rt_can_device *can, int cmd, void *arg)
                 if (filter_cfg->items[i].hdr == -1)
                 {
                     /* use default filter bank settings */
-                    /**
-                     * because can1 and can2 use the same filter groups, 
-                     * separate the groups of can1 and can2, to prevent being covered.
-                     */
                     if (drv_can->name == "can1")
                     {
                         /* can1 banks 0~13 */