[][Add export API ppe_del_entry_by_mac for wifi]

[Description]
Add export API ppe_del_entry_by_mac for wifi.
If not apply this patch, wifi call ppe_del_entry_by_mac will crash.
Keep the same with 4.x SDK.

[Release-log]
N/A

Change-Id: I77bbf12dd006d2fe48b43344edcdf0335ed7061f
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/5380973
diff --git a/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_hnat/hnat.c b/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_hnat/hnat.c
index 2479b3d..7a83d9a 100644
--- a/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_hnat/hnat.c
+++ b/target/linux/mediatek/files-5.4/drivers/net/ethernet/mediatek/mtk_hnat/hnat.c
@@ -34,6 +34,9 @@
 int (*ra_sw_nat_hook_tx)(struct sk_buff *skb, int gmac_no) = NULL;
 EXPORT_SYMBOL(ra_sw_nat_hook_tx);
 
+int (*ppe_del_entry_by_mac)(unsigned char *mac) = NULL;
+EXPORT_SYMBOL(ppe_del_entry_by_mac);
+
 void (*ppe_dev_register_hook)(struct net_device *dev) = NULL;
 EXPORT_SYMBOL(ppe_dev_register_hook);
 void (*ppe_dev_unregister_hook)(struct net_device *dev) = NULL;
@@ -198,7 +201,6 @@
 
 	return ret;
 }
-EXPORT_SYMBOL(entry_delete_by_mac);
 
 static void hnat_roam_handler(struct work_struct *work)
 {
@@ -562,6 +564,7 @@
 	if (hnat_register_nf_hooks())
 		return -1;
 
+	ppe_del_entry_by_mac = entry_delete_by_mac;
 	hook_toggle = 1;
 
 	return 0;
@@ -594,6 +597,7 @@
 	hnat_cache_ebl(1);
 
 	mod_timer(&hnat_priv->hnat_sma_build_entry_timer, jiffies + 3 * HZ);
+	ppe_del_entry_by_mac = NULL;
 	hook_toggle = 0;
 
 	return 0;