net: ethernet: mtk_eth_soc: Reuse value using READ_ONCE instead of re-rereading it

In mtk_flow_entry_update_l2, the hwe->ib1 is read using READ_ONCE at the
beginning of the function, checked, and then re-read from hwe->ib1,
may void all guarantees of the checks. Reuse the value that was read by
READ_ONCE to ensure the consistency of the ib1 throughout the function.
Signed-off-by: linke li <lilinke99@qq.com>
Link: https://lore.kernel.org/r/tencent_C699E9540505523424F11A9BD3D21B86840A@qq.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/mediatek/mtk_ppe.c

@@ -580,7 +580,7 @@ mtk_flow_entry_update_l2(struct mtk_ppe *ppe, struct mtk_flow_entry *entry)
 
 		idle = cur_idle;
 		entry->data.ib1 &= ~ib1_ts_mask;
-		entry->data.ib1 |= hwe->ib1 & ib1_ts_mask;
+		entry->data.ib1 |= ib1 & ib1_ts_mask;
 	}
 }