Fix the build-osx target for the depends subsystem
Fix the build-osx target for the depends subsystem

Summary: It was not updated as part of D3919 as it should.

Test Plan:
  cd depends
  make build-osx

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D4037

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