wifi(vts): Set the iface up as a part of setup

Attempts to fix a VTS test failure reported by OEM's on devices
supporting concurrent AP iface.

Bug: 143096362
Test: make vts && vts-tradefed run commandAndExit vts --module VtsHalWifiV1_0Host
Test: Will need to ask OEM to verify the fix.
Change-Id: I0958d720411258761f4ac5bcccc823b06a55d518
Merged-In: I0958d720411258761f4ac5bcccc823b06a55d518