TT#14008 allow null TABLE variable

If there's no config file present then retrieval of the table number
yields an empty string. Allow this as an expected case to silence a
warning from bash (using -lt against an empty string)

Change-Id: I0420d2e1c555f6b56a56fc5f47d3bc183a929e50
(cherry picked from commit 52c91f9ceb)

debian/ngcp-rtpengine-iptables-setup

@@ -39,7 +39,7 @@ fi
 
 firewall_setup()
 {
-  if [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
+  if [ -z "$TABLE" ] || [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
     return
   fi
 
@@ -66,7 +66,7 @@ firewall_setup()
 
 firewall_teardown()
 {
-  if [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
+  if [ -z "$TABLE" ] || [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
     return
   fi
 

pkg/deb/debian/rtpengine-iptables-setup

@@ -39,7 +39,7 @@ fi
 
 firewall_setup()
 {
-  if [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
+  if [ -z "$TABLE" ] || [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
     return
   fi
 
@@ -66,7 +66,7 @@ firewall_setup()
 
 firewall_teardown()
 {
-  if [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
+  if [ -z "$TABLE" ] || [ "$TABLE" -lt 0 ] || [ "$VIRT" = "yes" ]; then
     return
   fi