Normalize zte_zxros ARP Q-in-Q vlan names

[mjbear]

• EXTERNAL_VLAN becomes OUTER_VLAN
• INTERNAL_VLAN becomes INNER_VLAN
• Related to discussion on PR Add cisco_xr_show_running-config_interface #2241
  • (topic on Q-in-Q here)
  • ZTE ZXR10 command docs (pdf) - example below in table from page 17 (or 1-9 to 1-10 as numbered)
  • previous state of template and raw

Field	Description
IP Address	IP address.
Age	Aging time (P means permanent, and an number means the remaining aging time of the dynamic ARP entity) .
Hardware Address	MAC address.
Interface	Interface name.
Exter VlanID	External VLAN tag.
Inter VlanID	Internal VLAN tag.
Sub Interface	Sub-interface (physical port).