net: hns3: implement the IMP reset processing for PF

The current code only print the prompt message after receiving
the IMP reset interrupt and does not perform the corresponding driver
reset operation. This patch implements the missing IMP reset handling
in the driver.
1. The driver sets the HCLGE_STATE_CMD_DISABLE to stop sending command
   after receiving the IMP reset interrupt.
2. The driver needs to notify the hardware to reload the IMP firmware.
3. The IMP firmware reloading makes the reset time of hardware longer,
   so it is necessary to extend the driver's waiting time to wait for
   the hardware reset to complete.
4. In hclge_check_event_cause, IMP reset event should have higher
   priority than other events.

Also, after clearing HCLGE_STATE_CMD_DISABLE in the hclge_cmd_init(),
it needs to check whether there is a pending reset, if so, just set
the HCLGE_STATE_CMD_DISABLE back and return.

Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>