Exit on missing file argument

salt/common/tools/sbin/soup

@@ -788,6 +788,7 @@ main() {
   check_airgap
   if [[ $is_airgap -eq 0 && $UNATTENDED == true && -z $ISOLOC ]]; then
     echo "Missing file argument for unattended airgap upgrade."
+    exit 1
   fi
   echo "Checking to see if this is a manager."
   echo ""