nvme-pci: use unsigned for io queue depth

mainline inclusion
from mainline-5.9-rc1
commit 61f3b896
category: bugfix
bugzilla: 175286
CVE: NA

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

The NVMe PCIe declares module parameter io_queue_depth as int. Change
this to u16 as queue depth can never be negative. Now to reflect this
update module parameter getter function from param_get_int() ->
param_get_uint() and respective setter function with type of n changed
from int to u16 with param_set_int() to param_set_ushort(). Finally
update struct nvme_dev q_depth member to u16 and use u16 in min_t()
when calculating dev->q_depth in the nvme_pci_enable() (since q_depth is
now u16) and use unsigned int instead of int when calculating
dev->tagset.queue_depth as target variable tagset->queue_depth is of type
unsigned int in nvme_dev_add().

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Conflicts:
	drivers/nvme/host/pci.c
	[ Feature patch 3b6592f7("nvme: utilize two queue maps, one
	  for reads and one for writes") is not applied.
	  ed92ad37("nvme-pci: only set nr_maps to 2 if poll queues
	  are supported") is not applied.
	  aa22c8e6("nvme-pci: set ctrl sqsize to the device q_depth")
	  is not applied. ]

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>