fix flash attention

wan/modules/attention.py

@@ -276,7 +276,7 @@ def pay_attention(
             k=k,
             v=v,
             cu_seqlens_q= cu_seqlens_q,
-            cu_seqlens_kv= cu_seqlens_k,
+            cu_seqlens_k= cu_seqlens_k,
             seqused_q=None,
             seqused_k=None,
             max_seqlen_q=lq,
@@ -289,8 +289,8 @@ def pay_attention(
             q=q,
             k=k,
             v=v,
-            cu_seqlens_q= [0, lq],
-            cu_seqlens_kv=[0, lk],
+            cu_seqlens_q= cu_seqlens_q,
+            cu_seqlens_k= cu_seqlens_k,
             max_seqlen_q=lq,
             max_seqlen_k=lk,
             dropout_p=dropout_p,