ipmi-net: Restore the persisted iptables filter

If the persisted iptables filter exist restore the filter.

Tested: The iptables filter is restored when the phosphor-ipmi-net

Change-Id: I8486f2928374ae6ea1b164426c405462ba0eabc8
Signed-off-by: Tom Joseph <tomjoseph@in.ibm.com>
diff --git a/recipes-phosphor/ipmi/phosphor-ipmi-net/ipmi-net-firewall.sh b/recipes-phosphor/ipmi/phosphor-ipmi-net/ipmi-net-firewall.sh
new file mode 100644
index 0000000..ca32f98
--- /dev/null
+++ b/recipes-phosphor/ipmi/phosphor-ipmi-net/ipmi-net-firewall.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+if [ -f $IPTABLESRULE ]; then
+    iptables-restore < $IPTABLESRULE
+fi