MT#57719 Introduce the `media_unconfirm()` function
Introduce `media_unconfirm()` to do a selective handling
of medias to unkernelize the correlated to it streams.
This is analogue of the of the `__monologue_unconfirm()`
but for medias.
Change-Id: Id8ede0fc56412021c301e97764fd5dd070b7d484