[hack] Back out "[hack][oss] simplify hhi dependency"
[hack] Back out "[hack][oss] simplify hhi dependency"

Summary:
Original commit changeset: 99d7d945978f breaks OSS build because of a path
difference:
- hphp/hack/_build/default/... on devservers
- hphp/hack/default/... on real OSS setup

We should address that, but reverting for the time being

Reviewed By: andrewjkennedy

Differential Revision: D15080312

fbshipit-source-id: a6f726bc119d2a898114f2636c0b9fd251685fd6

samwgoldman/flow,mroch/flow,facebook/flow,facebook/flow,facebook/flow,mroch/flow,samwgoldman/flow,samwgoldman/flow,facebook/flow,mroch/flow,gabelevi/flow,mroch/flow,gabelevi/flow,samwgoldman/flow,samwgoldman/flow,gabelevi/flow,gabelevi/flow,gabelevi/flow,facebook/flow,samwgoldman/flow,gabelevi/flow,samwgoldman/flow,mroch/flow,facebook/flow,gabelevi/flow,facebook/flow,mroch/flow,mroch/flow