nvme-fc: use ctrl state getter

Do not access the state variable directly, instead use proper
synchronization so not stale data is read.

Fixes: e6e7f7ac ("nvme: ensure reset state check ordering")
Signed-off-by: Daniel Wagner <wagi@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>