Test for predictable device names

src/freedombone-utils-wifi

 # device names get assigned random names. This is a hacky workaround.
 # Also adding net.ifnames=0 to kernel options on bootloader may work.
 function enable_predictable_device_names {
-    ln -s /dev/null /etc/udev/rules.d/80-net-setup-link.rules
-    update-initramfs -u
+    test_predictable=$(ls -la /etc/udev/rules.d/80-net-setup-link.rules)
+    if [[ "$test_predictable" != *"/dev/null" ]]; then
+        ln -s /dev/null /etc/udev/rules.d/80-net-setup-link.rules
+        update-initramfs -u
+    fi
 }
 
 function wifi_is_running {