nfs: Fix nfs_access_get_cached_rcu() sparse error

This patch fixes the following sparse error:
fs/nfs/dir.c:2353:14: error: incompatible types in comparison expression (different address spaces):
fs/nfs/dir.c:2353:14:    struct list_head [noderef] <asn:4> *
fs/nfs/dir.c:2353:14:    struct list_head *
Signed-off-by: NMadhuparna Bhowmik <madhuparnabhowmik04@gmail.com>
Signed-off-by: NPaul E. McKenney <paulmck@kernel.org>

fs/nfs/dir.c

@@ -2383,7 +2383,7 @@ static int nfs_access_get_cached_rcu(struct inode *inode, const struct cred *cre
 	rcu_read_lock();
 	if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
 		goto out;
-	lh = rcu_dereference(nfsi->access_cache_entry_lru.prev);
+	lh = rcu_dereference(list_tail_rcu(&nfsi->access_cache_entry_lru));
 	cache = list_entry(lh, struct nfs_access_entry, lru);
 	if (lh == &nfsi->access_cache_entry_lru ||
 	    cred_fscmp(cred, cache->cred) != 0)