The doorbell update interfaces are very similar for different queues, such
as SQ, RQ, SRQ, CQ and EQ. So reorganize these code and also fix some
inappropriate naming.

Link: https://lore.kernel.org/r/1616840738-7866-3-git-send-email-liweihang@huawei.comSigned-off-by: NYixian Liu <liuyixian@huawei.com>
Signed-off-by: NWeihang Li <liweihang@huawei.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>