accel/habanalabs: add handling for unexpected user event

In order for the user to be aware of unexpected events in Gaudi2 that
aren't assigned to a specific engine, we are adding the handling of
this dedicated interrupt.

Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>