rbd: refactor GetImageNames to use a for loop instead of recursion
rbd: refactor GetImageNames to use a for loop instead of recursion

This is done because using a for loop is more idiomatic in Go code.

Signed-off-by: Sanford Miller <3436e170c9a0b84ab30cb4c0dacf0efe17e13dfa@digitalocean.com>

ceph/go-ceph,ceph/go-ceph,ceph/go-ceph