aq: Report partial initialization failures to iflib

[kbowling]

Summary

Stop initialization when hardware setup, ring initialization/start, or
datapath start fails. Run the existing best-effort stop/cache/reset
cleanup and report the failure through iflib_init_failed(). Do not keep
configuring later rings or publish the interface as running.

[nick_spun.io]

Whoops, we should definitely be bailing out in these spots, good catch!