Replace ip_link_add with setup_network.

The setup_network binary has some conditional logic to handle host
images that are VLAN-capable versus host images that aren't. Because
init scripts aren't set up for conditional logic, the logic is moved
into the implementation of the binary. The binary must be invoked with
an argument telling it whether or not to use vlans.

Bug: 111320496
Test: Ran cf_x86_phone-userdebug with and without vlans enabled.
Change-Id: Ied74940d30848ac32abd73a349c46a9e8b619edb
(cherry picked from commit d3fe8a4284e27ca8280b71431aebbce7d90bea94)
(cherry picked from commit fff3e91e2cc29ec2bccdc0990463cccb7ac53c83)
6 files changed