dmonitoringmodeld: fix black padding not black after libyuv.I420Scale (#22971)
dmonitoringmodeld: fix black padding not black after libyuv.I420Scale (#22971)

* true black

* set black once

* move def

* add commnet

* Update selfdrive/modeld/models/dmonitoring.cc

* Update selfdrive/modeld/models/dmonitoring.cc

* Update selfdrive/modeld/models/dmonitoring.cc

* Update selfdrive/modeld/models/dmonitoring.cc

Co-authored-by: Adeeb Shihadeh <560a1160cdca1405d17f7eea1cfe3906403d06ef@gmail.com>
commaai/openpilot,commaai/openpilot,commaai/openpilot,commaai/openpilot,commaai/openpilot,commaai/openpilot