nvme: ensure subsystem reset is single threaded

stable inclusion
from stable-v5.10.156
commit 023435a095d22bcbbaeea7e3a8c534b5c57d0d82
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7MCG1

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=023435a095d22bcbbaeea7e3a8c534b5c57d0d82

--------------------------------

commit 1e866afd upstream.

The subsystem reset writes to a register, so we have to ensure the
device state is capable of handling that otherwise the driver may access
unmapped registers. Use the state machine to ensure the subsystem reset
doesn't try to write registers on a device already undergoing this type
of reset.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=214771


Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>