net: qed: fix async event callbacks unregistering

commit 31333c1a upstream.

qed_spq_unregister_async_cb() should be called before
qed_rdma_info_free() to avoid crash-spawning uses-after-free.
Instead of calling it from each subsystem exit code, do it in one place
on PF down.

Fixes: 291d57f6

 ("qed: Fix rdma_info structure allocation")
Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>