habanalabs/gaudi2: fix log for sob value overflow/underflow

The value in SM_SEI_CAUSE includes the SOB index and not the SOB group
index.
Remove usage of log_mask in sm_sei_cause structure as it was never
used.

Signed-off-by: Carmit Carmel <ccarmel@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>