fabrics: Use corresponding hostid when hostnqn is generated

fabrics: Use corresponding hostid when hostnqn is generated

After the kernel commit ae8bd606e09b ("nvme-fabrics: prevent overriding
of existing host"), kernel ensures hostid and hostnqn maintain 1:1
mapping and "non 1:1 mapping will be rejected". This makes 'nvme
discover' and 'nvme connect' commands fail when they generate hostnqn,
since it does not use corresponding hostid.

To avoid the failures, prepare and use corresponding hostid to the
generated hostnqn, taking the hostid from the hostnqn string. Also add
checks for prepared hostnqn and hostid. If the hostid taken from the
generated hostnqn is different from the hostid from file, print a
warning message. Also, if the prepared hostnqn are inconsistent with the
prepared hostid, print a warning.

Link: https://lore.kernel.org/linux-nvme/l7vk7fnzltpmvkwujsbf2btrzip6wh7ug62iwa3totqcda25l6@siqx7tj6lt3l/
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Daniel Wagner <dwagner@suse.de>