net: prestera: acl: fix return value check in prestera_acl_rule_entry_find()

rhashtable_lookup_fast() returns NULL pointer not ERR_PTR().
Return rhashtable_lookup_fast() directly to fix this.

Fixes: 47327e19 ("net: prestera: acl: migrate to new vTCAM api")
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/prestera/prestera_acl.c

@@ -419,11 +419,8 @@ struct prestera_acl_rule_entry *
 prestera_acl_rule_entry_find(struct prestera_acl *acl,
 			     struct prestera_acl_rule_entry_key *key)
 {
-	struct prestera_acl_rule_entry *e;
-
-	e = rhashtable_lookup_fast(&acl->acl_rule_entry_ht, key,
-				   __prestera_acl_rule_entry_ht_params);
-	return IS_ERR(e) ? NULL : e;
+	return rhashtable_lookup_fast(&acl->acl_rule_entry_ht, key,
+				      __prestera_acl_rule_entry_ht_params);
 }
 
 static int __prestera_acl_rule_entry2hw_del(struct prestera_switch *sw,