RQT objects require that a power of two value be configured for both
rqt_max_size and rqt_actual size.

For create_rqt, make sure to round up to the power of two the value of
given by the user who created the vdpa device and given by
ndev->rqt_size. The actual size is also rounded up to the power of two
using the current number of VQs given by ndev->cur_num_vqs.

Same goes with modify_rqt where we need to make sure act size is power
of two based on the new number of QPs.

Without this patch, attempt to create a device with non power of two QPs
would result in error from firmware.

Fixes: 52893733 ("vdpa/mlx5: Add multiqueue support")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Message-Id: <20220912125019.833708-1-elic@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>