This change introduces support for the vlan_limit option.
This parameter is currently set to 1 by default, but we should set
it to 2 to enable vlan_transparent, which requires nested vlans.
Related-Bug: #1918418
Change-Id: Id9aaab2a1e3ad2d2d43cd5cddf389d20abaf4461
(cherry picked from commit 4887f4ccd6)
14011d69c1