net: hns3: initialize CPU reverse mapping

Allocate CPU rmap and add entry for each irq. CPU rmap is
used in aRFS to get the queue number of the rx completion
interrupts.

In additional, remove the calling of
irq_set_affinity_notifier() in hns3_nic_init_irq(), because
we have registered notifier in irq_cpu_rmap_add() for each
vector, otherwise it may cause use-after-free issue.

Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>