I don't remember any of the prisoner making any comment about Bruce Wayne while he is kept captive in the pit.
Therefore, I would think that nobody knows who he is.
After all, they are prisoners with few information coming from the outside world. Furthermore, their prison is in a country far away from where Bruce Wayne's activities are famous.
When he escapes, the prisoners cheer up not for who he is, but for what he has done : beaten the pit and showed all the prisoners that it was possible to escape, thus giving them great hope.