nvme-rdma: fix nvme_rdma_create_queue_ib error flow

QP object is created using rdma_cm api, therefore the destruction
should use the same api for symmetry.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>