accel/habanalabs: additional print in device-in-use info

accel/habanalabs: additional print in device-in-use info

When device release triggers a hard reset, there is a printout of
the cause. Currently listed causes (that increment context refcount)
are active command submissions and exported DMA buffer objects. In
any other case, the printout emits "unknown reason". We identify and
print another reason - allocated command buffers.

Signed-off-by: Ilia Levi <illevi@habana.ai>
Reviewed-by: Ofir Bitton <obitton@habana.ai>
Signed-off-by: Ofir Bitton <obitton@habana.ai>