qed: SPQ async callback registration

Whenever firmware indicates that there's an async indication it needs
to handle, there's a switch-case where the right functionality is called
based on function's personality and information.

Before iWARP is added [as yet another client], switch over the SPQ into
a callback-registered mechanism, allowing registration of the relevant
event-processing logic based on the function's personality. This allows
us to tidy the code by removing protocol-specifics from a common file.

Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>