RDMA/hns: Fix wrong field of SRQ number the device supports

The SRQ capacity is got from the firmware, whose field should be ended at
bit 19.

Fixes: ba6bb7e9 ("RDMA/hns: Add interfaces to get pf capabilities from firmware")
Link: https://lore.kernel.org/r/1606382812-23636-1-git-send-email-liweihang@huawei.com


Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>