habanalabs: fixes to the poll-timeout macros

- use conventional internal macro variables (double underscore prefix)
- adjust address casting
- on register poll using ELBI use ELBI read rather than BAR read on
  error condition
- remove unused macro

Signed-off-by: Ohad Sharabi <osharabi@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>