RDMA/hns: Fix sleeping in setup_dca_buf_to_hw()

driver inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6GT7F



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setup_dca_buf_to_hw() was in a spinlock which is a kind of atomic
context.

Replace the kvcalloc() with no sleep kcalloc()

Fixes: 12aa71f8 ("RDMA/hns: Add DCA support for kernel space")
Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>