[PATCH 2/3] nvme-core: don't check non-mdts for disc ctrl

[Sagi Grimberg]

>> Don't check the non mdts limits for the discovery controller as we
>> don't support I/O command set, this also masks the following warning
>> reported by the nvme_log_error() when running blktest nvme/002: -
> 
> I think we can skip the whole call to nvme_init_non_mdts_limits in this
> case.  And we should probably key it off having I/O queues to also
> cover administrative controllers.

I'd also move this check to the call-site instead of where it is now.