nvme: remove IDENTIFY_CNS quirk from normal QEMU SSDs

The IDENTIFY_CNS quirk was applied as part of QEMU
OCSSD handling in commit 6442451b.  But it was applied
not only to the OCSSD dev ID, but also the dev ID
for non-OCSSD NVMe controllers.

Starting with QEMU 5.2, QEMU will allocate a default
256 namespaces, but only some are active (associated
with the backing disks specified by the user).  QEMU
supports IDENTIFY_CNS, but since this quirk was set,
we wouldn't send a real IDENTIFY_CNS and instead
would just populate a fake list where all namespaces
were considered active.  This causes breakage in
a few places - mainly where we iterate through
the active namespaces, and then are surprised that
calling spdk_nvme_ns_is_active() returns false.

It was also breaking bdev_nvme_attach_controller RPC,
since by default we can only support returning 128
names, but since all of the namespaces were deemed
active, it was trying to return 256.

Fixes #1916.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I4fdd27e0e36f0ac07a95f9f29aa83357e8505a45

Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/7658


Community-CI: Mellanox Build Bot
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>