hazptr: Rename await_zero_bulk_reclaims to wait_for_bulk_reclaim
hazptr: Rename await_zero_bulk_reclaims to wait_for_bulk_reclaim

Summary: Change name to reserve the word await for coroutines.

Reviewed By: yfeldblum

Differential Revision: D8076750

fbshipit-source-id: 38771dc22c39e194888ac272299ec1ae83df6389

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