NFS: Don't allocate nfs_fattr on the stack in __nfs42_ssc_open()

stable inclusion
from stable-v5.10.140
commit 23c6f25a60435f85e1a442dd5492e96a260dd731
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I63FTT

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=23c6f25a60435f85e1a442dd5492e96a260dd731



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[ Upstream commit 156cd285 ]

The preferred behaviour is always to allocate struct nfs_fattr from the
slab.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>