[Feature][ZXW-241]merge P56U01 version

Only Configure: No
Affected branch: master
Affected module: unknow
Is it affected on both ZXIC and MTK: only ZXIC
Self-test: Yes
Doc Update: No

Change-Id: I7985538dde6951dd824c36149bf9a1e3ca23c734
diff --git a/ap/app/Script/scripts/psext_updown.sh b/ap/app/Script/scripts/psext_updown.sh
index 56f4103..9f74350 100755
--- a/ap/app/Script/scripts/psext_updown.sh
+++ b/ap/app/Script/scripts/psext_updown.sh
@@ -438,8 +438,11 @@
 }
 
 if [ "-$1" == "-linkup" ]; then
-	mtu=`nv get mtu`
-	ifconfig $ps_if mtu $mtu
+	ra_mtu_enable=`nv get ra_mtu_enable`
+	if [ "$ra_mtu_enable" != "1" ]; then
+		mtu=`nv get mtu`
+		ifconfig $ps_if mtu $mtu
+    	fi
 	if [ "-$ps_ext_mode" == "-1" ]; then
         brctl addbr $ext_br
         brctl setfd $ext_br 0.1