RDMA/bnxt_re: add helper function __poll_for_resp

This interface will be used if the driver has not enabled interrupt
and/or interrupt is disabled for a short period of time.
Completion is not possible from interrupt so this interface does
self-polling.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1686308514-11996-10-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>