nfsd: don't alloc under spinlock in rpc_parse_scope_id

stable inclusion
from stable-5.10.80
commit f3492c4a92644cb54ec2c6daff6c428aebfc36dc
bugzilla: 185821 https://gitee.com/openeuler/kernel/issues/I4L7CG

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f3492c4a92644cb54ec2c6daff6c428aebfc36dc



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[ Upstream commit 9b6e27d0 ]

Dan Carpenter says:

  The patch d20c11d8: "nfsd: Protect session creation and client
  confirm using client_lock" from Jul 30, 2014, leads to the following
  Smatch static checker warning:

        net/sunrpc/addr.c:178 rpc_parse_scope_id()
        warn: sleeping in atomic context

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: d20c11d8 ("nfsd: Protect session creation and client...")
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Reviewed-by: Weilong Chen <chenweilong@huawei.com>
Acked-by: Weilong Chen <chenweilong@huawei.com>

Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>