nvme: Make nvme_uninit_ctrl symmetric to nvme_init_ctrl

mainline inclusion
from mainline-v5.7-rc1
commit 726612b6
category: bugfix
bugzilla: NA
CVE: NA
Link: https://gitee.com/openeuler/kernel/issues/I1WGZE



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

Put the ctrl reference count at nvme_uninit_ctrl as opposed to
nvme_init_ctrl which takes it. This decrease the reference count at the
core layer instead of decreasing it on each transport separately.
Also move the call of nvme_uninit_ctrl at PCI driver after calling to
nvme_release_prp_pools and nvme_dev_unmap, in order to put the reference
count after using the dev. This is safe because those functions use
nvme_dev which is freed only later at nvme_pci_free_ctrl.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Conflicts:
    drivers/nvme/host/tcp.c
    drivers/nvme/host/core.c
[No code about TCP in current version and adjust context.]
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Jike Cheng <chengjike.cheng@huawei.com>
Signed-off-by: Lijie <lijie34@huawei.com>
Reviewed-by: Hou Tao <houtao1@huawei.com>
Acked-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>