NFSD: nfsd_file_hash_remove can compute hashval

[ Upstream commit cb7ec76e ]

Remove an unnecessary use of nf_hashval.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>