onnxifi: make it work with AsyncIf
Summary:
the onnxifi path didn't handle the input/output name rewrite for ssa correctly for AsyncIf op. Add support for it.
Also fixed a place where we lose the net type while doing onnxifi transform.
Test Plan: Load 163357582_593 which is a multi feed model that uses AsyncIf. This used to fail with c2 not finding some blobs in workspace. Now it works.
Reviewed By: dhe95
Differential Revision: D21268230
fbshipit-source-id: ce7ec0e952513d0f251df1bfcfb2b0250f51fd94
