Rather than embedding adminq directly in the spdk_nvme_ctrlr structure,
change it to a pointer to a spdk_nvme_qpair. This is necessary to allow
the transport to extend the qpair structure.
Change-Id: I041685d5037088cf56d046fe99bf204edcfc57b1
Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>