Expose struct ice_aq_task to callers,
what takes burden of memory ownership out from AQ-wait family of functions,
and reduces need for heap-based allocations.

Embed struct ice_rq_event_info event into struct ice_aq_task
(instead of it being a ptr) to remove some more code from the callers.

Subsequent commit will improve more based on this one.
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>