tree: Add nvme_root identify flag to scan NVMe topology

[ikegami-t]

This is to avoid nvme identify namespace to scan NVMe topology.

[ikegami-t]

The nvme identify namespace done by the sysfs ns nuse ns_head_update_nuse() and ns_update_nuse() as below.
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/nvme/host/sysfs.c#n201

[igaw]

The nvme identify namespace done by the sysfs ns nuse ns_head_update_nuse() and ns_update_nuse() as below. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/nvme/host/sysfs.c#n201

This should have been in the commit message explaining why the change is needed. This is important for anyone later to figure out why we added a change.

[ikegami-t]

Okay will update the commit message later.

[igaw]

I am still pondering how to address this. The change is quite big in order to pass down a simple flag. I wonder if some sort of refactoring is necessary first.

[hreinecke]

Instead of passing flags we should drop the call to 'nvme_scan()' and use the device name directly. Much like we already do for eg 'nvme reset'.

[igaw]

We don't need this anymore, fixed it differently: linux-nvme/nvme-cli@a31081a