nvme: fix admin queue leak on controller reset

nvme: fix admin queue leak on controller reset

When nvme_alloc_admin_tag_set() is called during a controller reset,
a previous admin queue may still exist. Release it properly before
allocating a new one to avoid orphaning the old queue.

This fixes a regression introduced by commit 03b3bcd319b3 ("nvme: fix
admin request_queue lifetime").

Cc: Keith Busch <kbusch@kernel.org>
Fixes: 03b3bcd319b3 ("nvme: fix admin request_queue lifetime").
Reported-and-tested-by: Yi Zhang <yi.zhang@redhat.com>
Closes: https://lore.kernel.org/linux-block/CAHj4cs9wv3SdPo+N01Fw2SHBYDs9tj2M_e1-GdQOkRy=DsBB1w@mail.gmail.com/
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>