rbd: rename mapOptions and options argument slices
rbd: rename mapOptions and options argument slices

With the new support for passing --options, referring to ExecCommand()
argument slices as mapOptions and options is confusing.

Signed-off-by: Ilya Dryomov <152d4c5bebf13a5b809d42b4d789cf9d887e6698@gmail.com>

ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi